European Nuclear Physics Conference 2022 (EuNPC 2022)

24 Oct 2022, 08:30 → 28 Oct 2022, 14:30 Europe/Madrid

Facultad de Ciencias de la Comunicación (University of Santiago de Compostela)

Dolores Cortina, Elena Ferreiro, Elena Mora, Rubén Díaz Fernández

EuNPC2022 is the fifth European Nuclear Physics Conference, organized by the Nuclear Physics Division of the European Physical Society, the Nuclear Physics Group of the  Real Sociedad Española de Física  and  the Instituto Galego de Física de Altas Enerxías of Santiago de Compostela University. The conference will take place from October 24th - 28th 2022, and will be held in Santiago de Compostela.

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Monday 24 October

REGISTRATION

WELCOME

Plenary Talks

1 Observation of the tetra neutron in the p(p, α) reaction at large momentum transfer

The experimental search for the existence of a tetra neutron state has a long history, and the situation remained unclear until recently, and a possible explanation of our experimental finding is still open. On the theoretical side, large efforts have been undertaken as well recently, with results and predictions scattering over wide range in energy, including the prediction for the non-existence of a bound or resonance state. The experimental challenge is to create an isolated 4-neutron system in the final state, without low-energy final-state interaction with other particlesinvolved in the reaction. We have employed a new experimental approach for the search of a possible tetra neutron, the quasi free ${}^8$He($p$,$p\alpha$)4n reaction at high beam energy. The experiment selected the knockout of the alpha particle at very large momentum transfer, corresponding to 180° $p - \alpha$ scattering in the c.m. frame, separating the charged particles from the neutrons in momentum space.

The experiment has been carried out at the SAMURAI setup located at the RIBF. The scattered charged particles have been detected and momentum analysed, from which the missing mass spectrum has been reconstructed in a wide energy window accepted by the experiment. In case of the absence of any interaction among the neutrons in the final state, a wide distribution centred around 30 MeV relative energy was expected, which reflects the internal relative motion of the neutrons in ${}^8$He. It was indeed found, that the largest fraction of the cross section corresponds to this shape. In addition, a well pronounced resonance-like peak at 2 MeV energy with a width of about 2 MeV has been observed with a larger than 5 sigma significance, providing clear evidence for strong four-neutron correlations in the final state. The results have been published recently in Nature [1]. The experiment and results will be presented and discussed.

[1] M. Duer et al., Nature 606 (2022) 678

Speaker: Thomas Aumann (T)

2 High resolution gamma-ray spectroscopy of Exotic nuclei.

The AGATA (Advanced GAmma Tracking Array) $\gamma$-ray array [1] has been celebrating its first ten years of data taking all over Europe. Thanks to its unprecedented position and energy resolution combined with state-of-the-art complementary instrumentation, AGATA has allowed to pave the way towards high precision spectroscopy measurements in exotic nuclei, thus providing a wealth of structural information far away from the stability line

Recently, the array has made its comeback to the Legnaro National Laboratories (LNL, Italy), where it is expected to be used both with stable and post-accelerated radioactive beam produced by the SPES facility. The first campaign of AGATA at LNL started in Spring 2022 [2] with stable beams and AGATA coupled to the PRISMA large acceptance spectrometer and additional charged particle detectors. In this talk, a review on the achievements in nuclear structure physics and future physics campaigns with the $\gamma$-ray tracking AGATA will be presented.

[1] A. Akkoyun et al., NIM A 668, 26 (2012).

[2] J.J. Valiente Dobon et al, In preparation

Speaker: Alain Goasduff (INFN - LNL)

goasduff_eunpc2022_gamma.pdf

11:10 Coffee Break

Plenary Talks

3 Present and future accelerators for nuclear physics

Accelerators for nuclear physics research span a wide parameter range in beam energy and intensity. We provide an overview of the existing and planned accelerators, design considerations, performance limitations and technology developments that enable future machines.

Speaker: Wolfram Fischer (Brookhaven National Laboratory)

2022-10-24 EuNPC - NP accelerators.pdf

2022-10-24 EuNPC - NP accelerators.pptx

4 Status and Perspectives of Silicon Detectors

A review of the present status of silicon tracking and vertexing systems and their future developements will be presented. We will show themodern detectors used in present day experiments both in nuclear and elementary particle physics, and the achieved results. Then show the near-future systems which are now being designed, built, or commissioned. And in conclusion an outlook on the future developments for next-generation silicon detectors will be presented.

Speaker: Alberto Cervelli (Universita e INFN, Bologna (IT))

Cervelli_EuNPC.pdf

5 Development of novel detector concepts for nuclear physics with rare isotope beams at FRIB

Since their invention in the 1930s, particle accelerator science has led to major discoveries and advancements in high-energy physics, nuclear physics, and other fields. Progress in accelerator-based experimental physics has always been linked to improvement of detector technology. Rare isotope (RI) beam facilities are now important tools for nuclear physics. The Facility for Rare Isotope Beams (FRIB), located on the campus of the Michigan State University, is a new world-leading user facility for the study of RIs using the in-flight fragmentation method. The unprecedented potential discovery of a modern rare isotope beam facility, such as FRIB, can only be realized by implementing state-of-the-art experimental equipment capable of studying these isotopes at a high beam rate and high performance.
In this work, I report the development of a few innovative detector concepts for tracking and particle identification (PID) of heavy-ions. In particular, I will describe the development of new micro-pattern gaseous detector (MPGD) structures capable of stable, high-gain operation at low-pressure, applied as either position-sensitive readout for Time-Projection-Chamber in active-target mode (AT-TPC), or for drift chambers at the focal-plane of large-acceptance spectrometer.
In addition, I will present the progress on design and construction of advanced, innovative instrumentation for highly accurate and efficient identification of the atomic number (Z) of nuclei transmitted to the focal plane of high-resolution spectrographs. The detector concept is based on event-by-event Energy-Loss measurement in a multi-segmented Optical Scintillator System (ELOSS), by recording the scintillation light released by a charged particle along its track. We discuss the optimization of the optical readout configuration based on DUV-sensitive PhotoMultiplier Tubes (PMTs), the expected performance of the novel detector concept, and the overall impact on radiation-detection physics and technology applied to the field of experimental nuclear physics with rare-isotope beams.

Speaker: Dr Marco Cortesi (Facility for Rare Isotope Beams)

Cortesi_EuNPC2022.pdf

Cortesi_EuNPC2022.pptx

13:20 Lunch Break

Lise Meitner Award Ceremony

Social Activity: Lise Meitner Project

Tuesday 25 October

Plenary Talks

6 Cosmic laboratories for nuclear physics

In 2017, a multimessenger era started with the first gravitational wave detection from the merger of two neutron stars (GW170817) and the rich electromagnetic follow-up. The most exciting electromagnetic counterpart was the kilonova. This provides an answer to the long-standing question of how and where heavy elements are produced in the universe. The neutron-rich material ejected during the neutron star merger (NSM) undergoes an r-process (rapid neutron capture process) that produces heavy elements and a kilonova. Moreover, observations of abundances from the oldest stars reveal an additional r-process contribution of a rare and fast event, which could be core-collapse supernovae (CCSN) with strong magnetic fields, so called magneto-rotational supernovae (MR-SN). Now we can use NSM and CCSN as cosmic laboratories to test nuclear physics under extreme conditions and to understand the origin and history of heavy elements. We combine hydrodynamic simulations of NSM and MR-SN including state-of-the-art microphysics, with nucleosynthesis calculations involving extreme neutron-rich nuclei, and forefront observations of stellar abundances in the Milky Way and in orbiting dwarf galaxies. This opens up a new frontier to use the freshly synthesized elements to benchmark simulations against observations. The nucleosynthesis depends on astrophysical conditions (e.g., mass of the neutron stars) and on the microphysics included (equation of state and neutrino interactions). Therefore, comparing calculated abundances based on simulations to observations of the oldest stars and future kilonovae will lead to ground-breaking discoveries for CCSN, NSM, the extreme physics involved, and the origin of heavy elements.

Speaker: Almudena Arcones

arcones.pdf

7 Proton capture on stored radioactive ions

By combining two unique facilities at GSI (Helmholtz Centre for Heavy Ion Research),
the fragment separator (FRS) and the experimental storage ring (ESR), the first direct measurement of a proton capture reaction of a stored radioactive isotope has been accomplished. The combination of sharp ion energy, ultra-thin internal gas target, and the ability to adjust energy of the beam in the ring enables precise, energy-differentiated measurements of the (p,𝛾)-cross-sections. Our new results provide a sensitive method for measuring (p,𝛾) and (p,n) reactions relevant for nucleosynthesis processes in supernovae, which are among the most violent explosions in the universe and are not yet well understood.

The cross section of the 118Te(p,𝛾) reaction was measured at energies of astrophysical interest. The heavy ions were stored with energies of 6 MeV/nucleon and 7 MeV/nucleon and interacted with a hydrogen jet target. The produced 119I ions were detected with double-sided silicon strip detectors. The radiative recombination process of the fully stripped 118Te ions and electrons from the hydrogen target was used as a luminosity monitor.

These measurements follow a proof-of-principle experiment which was performed in 2016 to validate the method on the stable isotope 124Xe [1].
An overview of the experimental method and preliminary results from the ongoing analysis will be presented.

[1] J. Glorius et al., Phys. Rev. Lett. 122, 092701 (2019)

Speaker: Sophia Florence Dellmann (Goethe University Frankfurt)

EuNPC_SophiaDellmann.pptx

8 Nuclear Astrophysics at the Low-Energy Frontiers: Updates from underground laboratories

Nuclear fusion reactions are the heart of nuclear astrophysics: they sensitively influence the nucleosynthesis of the elements in the earliest stages of the Universe and in all the objects formed thereafter; control the associated energy generation and neutrino luminosity; influence the evolution of stars. LUNA (Laboratory for Underground Nuclear Astrophysics) is an experimental approach for the study of nuclear fusion reactions based on an underground accelerator laboratory.
The LUNA Collaboration has been directly measuring cross sections of nuclear processes belonging to Hydrogen, Helium burning and Big Bang Nucleosynthesis relevant in several astrophysical scenarios with unprecedented sensitivity, due to the huge background suppression available in the underground Gran Sasso Laboratories. In this talk, after a general introduction, the latest LUNA results and ongoing measurements will be presented.
Future researches will be carried out in the framework of the new LUNA-MV experiment as well as in several other underground laboratories. I will give an update with the status of new laboratories as well as future plans.

Speaker: Francesca Cavanna (Istituto Nazionale di Fisica Nucleare, sezione di Torino)

Cavanna_EUNPC2022_f.pdf

10:15 Coffee Break

Plenary Talks

9 Hadron Spectroscopy: an experimental overview

The spectrum of hadrons is composed of bound states of quarks and gluons. The distinctive property of confinement in strong interactions, which are described by Quantum Chromo-Dynamics (QCD), prevents quarks and gluons from appearing as free particles. A new generation of dedicated experiments in hadron physics has been proposed with the aim of uncovering properties of strong interactions and specifically the mysteries of confinement. Some of these experiments are already in operation and several more are planned for the near future in the main EU laboratories (CERN, Mainz, Bonn, GSI) and abroad (JLab/US, BESIII/China, JPARC/Japan, Belle/Japan). In this contribution, I will report the latest experimental results in hadron spectroscopy and plans for the future.

Speaker: Marco Andrea Battaglieri (INFN e Universita Genova (IT))

EUNPC22-Battaglieri.pdf

10 Unraveling the internal structure of the nucleon at Jefferson Lab and the future EIC

Understanding Quantum Chromodynamics (QCD) at large distances remains one of the main outstanding problems of nuclear physics. Investigating the internal structure of hadrons probes QCD in the non-perturbative domain and can help unravel the spatial extensions of nature's building blocks. Deeply Virtual Compton Scattering (DVCS) is the easiest reaction that accesses the Generalized Parton Distributions (GPDs) of the nucleon. GPDs offer the exciting possibility of mapping the 3-D internal structure of protons and neutrons by providing a transverse image of the constituents as a function of their longitudinal momentum. A vigorous experimental program is currently pursued at Jefferson Lab (JLab) to study GPDs through DVCS. New results recently published will be shown and discussed. We will give with an outlook on the Upgrade of JLab to 12 GeV, which will allow the full exploration of the valence quark structure of nucleons and nuclei and promises the extraction of full tomographic images. We will conclude discussing the future Electron-Ion Collider (EIC), which will complete this program by studying the gluon content of nucleons and nuclei.

Speaker: Carlos MUNOZ CAMACHO (IJCLab-Orsay (CNRS/IN2P3, France))

talk.pdf

11 Hadron spectroscopy from lattice QCD: progress and prospects

The status of lattice hadron spectroscopy will be discussed. In recent years there has been significant progress in calculations of the properties of exotic and conventional hadronic resonances and an overview of the challenges as well as the prospects for future studies will be presented.

Speaker: Sinead Ryan (Trinity College Dublin)

SRyan.pdf

NuPECC

12 NuPECC Long Range Plan 2024 for Nuclear Physics in Europe

The Nuclear Physics European Collaboration Committee (NuPECC) [1] hosted by the European Science Foundation represents today a large nuclear physics community from 22 countries, 3 ESFRI (European Strategy Forum for Research Infrastructures) nuclear physics infrastructures and ECT* (European Centre for Theoretical Studies in Nuclear Physics and Related Areas), as well as from 4 associated members and 9 observers.
The Committee, as one of its major activity, organises a consultation of the community leading to the definition and publication of a Long Range Plan (LRP) of European nuclear physics. To this aim, NuPECC has in the past produced five LRPs: in November 1991, December 1997, April 2004, December 2010 and November 2017 [2]. The LRP identifies opportunities and priorities for nuclear science in Europe and provides national funding agencies, ESFRI and the European Commission with a framework for coordinated advances in nuclear science in Europe. It serves also as a reference document for the strategic plans for nuclear physics in the European countries.
NuPECC published in February 2022 an assessment of the implementation of the LRP 2017 [1] which summarises achievements in nuclear science and techniques resulting from the LRP recommendations.
At its recent meeting in May 2022, NuPECC took the decision to launch the process of creating a new Long Range Plan for Nuclear Physics in Europe, identifying opportunities and priorities for nuclear science in Europe, with the aim of publishing the document in 2024[3]. With the intention of strengthening the bottom-up approach that has always played an important role in its LRPs, NuPECC has opened recently a call for inputs to the next LRP in form of short (5 page) documents describing the view of collaborations, experiments, or communities on the key topics for the next 10 years to be included in the upcoming LRP. The committee also solicits new ideas going beyond the topics considered in the LRP2017 or/and exploring synergies with the particle physics and astroparticle physics communities and considering new developments such as gravitational waves and multi-messenger astronomy. Contributions related to novel applications in cross disciplinary fields are also welcome. Nuclear Physics is a cross-continent field of science and European scientists strongly participate in the research activities outside of Europe. Inputs reflecting these activities are warmly welcome, too. The call for inputs will be open until 1 October 2022. Details concerning the submission procedure and the format of inputs can be found at the submission Web page [4].
The Steering Committee of the LRP2024, supervising the whole process, and all NuPECC members encourage active participation of the whole community in the elaboration of an ambitious and achievable strategic plan for the future of European nuclear physics.
References
[1] http : //nupecc.org .
[2] http : //nupecc.org/pub/lrp17/lrp2017.pdf .
[3] http : //nupecc.org/?display = lrp2024/main .
[4] https : //indico.ph.tum.de/event/7050/ .

Speaker: Prof. Marek Lewitowicz (GANIL/NuPECC)

NuPECC EuPNC 2022 Marek Lewitowicz 25102022_s.pdf

13:00 Lunch Break

Poster Session + Coffee

P1 Accelerators and Instrumentation

13 Warsaw Active-Target TPC: a new detector for photonuclear reactions studies at astrophysical energies

An active-target time-projection chamber (TPC) optimized for studying nuclear reactions of astrophysical interest has been developed by the University of Warsaw in collaboration with University of Connecticut and ELI-NP/IFIN-HH. The experimental program focuses on $(\mathrm{p},\gamma)$ and $(\alpha,\gamma)$ reactions that regulate the ratio of carbon and oxygen and those that burn $^{18}$O and, therefore, regulate the ratio between $^{16}$O and $^{18}$O in the Universe. In particular, the benchmark reaction of $^{12}$C$(\alpha,\gamma)^{16}$O can be studied at energies down to 1$\,$MeV in the centre-of-mass reference frame.

The cross-sections of time-reverse processes are measured using TPC detection technique by reconstructing energies and angular distributions of the charged products of photo-disintegration reactions induced by intense, monochromatic and collimated gamma-ray beams. Different reactions can be studied by tuning composition and density of the gaseous target for particular energy of the gamma beam.

The Warsaw TPC detector has an active volume of about 33$\,\times\,$20$\,\times\,$20$\,$cm$^3$ that is centered around the beam axis. The micro-pattern structures are employed to amplify the primary ionization induced by charged particles produced in reactions in the gaseous target. The 3D kinematics of charged particles in the event are reconstructed from signal strips, arranged into 3-coordinate redundant system. A total of about $10^3$ channels is read out by digitizing front-end electronics based on the Generic Electronics for TPCs (GET).

In years 2021-22 two pilot experiments were carried out to study $^{16}$O$(\gamma,\alpha)^{12}$C reaction using low-pressure CO$_2$ gas target and monochromatic gamma-ray beams at the Van der Graaf accelerator at IFJ-PAN, Cracow, Poland and at the High Intensity Gamma-Ray Source (HI$\gamma$S) facility, TUNL, Durham (NC), USA. The gamma beam energies ranged from 13.9$\,$MeV down to 8.51$\,$MeV (E$_{CM}$ from 6.7$\,$MeV down to 1.35$\,$MeV, respectively). In this work the principles of detector operation and basic track reconstruction methods will be discussed, together with preliminary results.

Speaker: Dr Mikolaj Cwiok (University of Warsaw (PL))

cwiok_slides_EuNPC2022.pdf

14 Highly-sensitive photodetachment spectroscopy in an MR-ToF device

The electron affinity (EA) reflects the energy released when an electron is attached to a neutral atom. An experimental determination of this quantity serves as an important benchmark for atomic models describing electron-correlation effects [1]. A comprehensive understanding of these effects is also necessary for accurate calculations of the specific mass shift, which is required to extract nuclear charge radii from measurable total isotope shifts. However, isotope shifts in the EA have been experimentally determined only for very few stable nuclides so far, and only with modest precision. As an example, the isotope shift between the two stable chlorine (Cl) isotopes is more precisely predicted in theory [2] than experimentally measured [3].

Exploiting the low-energy version of the Multi Ion Reflection Apparatus for Collinear Laser Spectroscopy (MIRACLS) [4], we have initiated a high-precision measurement of the isotope shift in the electron affinity between stable Cl isotopes as well as the long-lived $^{36}$Cl isotope. This can be achieved by photodetachment threshold spectroscopy of negative Cl ions. By trapping ion bunches between the two electrostatic mirrors of MIRACLS’ multi-reflection time-of-flight (MR-ToF) device, the same ion bunch can be probed by the spectroscopy laser repeatedly. As a result, the photodetachment efficiency can be significantly increased in comparison with single-pass experiments. Thus, instead of conventionally used pulsed high-power lasers with a large linewidth, narrow-bandwidth continuous-wave (CW) lasers can be employed. Consequently, the measurement precision is improved.

By confining the Cl- ions for several 10,000s of revolutions in the MR-ToF device, the residual atoms in the photodetachment process have been experimentally detected. For wavelengths only 3 nm above threshold, a CW laser power as low as 0.8 mW is demonstrably sufficient to observe the process of photodetachment. The first experimental data shows that the signal sensitivity of the new method is 3 to 4 orders of magnitude higher compared to conventional single-pass photodetachment experiments, see e.g. [1]. A first cross section curve of $^{35}$Cl was obtained providing confidence in the application of the new technique for high-precision isotope shift measurements between $^{35,37}$Cl, which are currently in preparation.

Due to its small floor space of just 2m x 1m, an MR-ToF apparatus can be easily installed at existing radioactive ion beam facilities. Combined with CW lasers operated at higher laser power, the MR-ToF technique will hence allow measurements of EAs and isotope shifts in the EA for various radioactive negative ions for the very first time as well as increasing the precision of existing measurements. Those new measurements will then serve as important benchmarks for theoretical models to e.g. decrease the uncertainty on the specific mass shift, which is often a leading contribution for the extraction of nuclear charge radii from measurable total shifts.

The novel technique will be introduced and the first experimental results will be presented.

[1] D. Leimbach et al., Nat Commun 11, 3824 (2020).
[2] T. Carette and M.R. Godefroid, J. Phys. B 46, 9 (2013).
[3] U. Berzinsh et al., Phys. Rev. A 51, 231(1995).
[4] F. Maier et al., Hyperfine Interact. 240, 54 (2019)
S. Sels et al., Nucl. Instr. Meth. Phys. Res. B 463, 310 (2020).
V. Lagaki et al., Nucl. Instr. Meth. Phys. Res. A 1014, 165663 (2021).

Speaker: Franziska Maria Maier (Universität Greifswald)

EuNPCnegions2.pdf

EuNPCnegions.pdf

EuNPCnegions.pptx

15 Experimental study of a discretized position circuit (DPC) network using an array of SiPMs

To simplify data acquisition electronics when using detectors composed of tens of SiPMs, and still being able to reconstruct positioning information, it is still very common to employ a resistor network. Good results are obtained with the DPC (Discretized Positioning Circuit) configuration, in which each SiPM of the array is connected to one node in a row of resistors, with a column of resistors at each end that connects the rows. Although this is the simplest topology and yields very good peak/valley ratios, it has the disadvantage that the charge division is asymmetric in X and Y directions, and that the different paths of the signal to reach the output, depending on the position of the event, introduce a barrel distortion in the image when the number of rows grows beyond, say, four lines. This can be minimized with a non-homogeneous choice of resistors in the network. We have developed a framework to optimize resistor values of DPC configurations for any number of rows, further imposing that all the SiPMs in the network ‘see’ an impedance to ground as similar as possible, in order to keep the shape of the pulse signal irrespectively of the position of the event. We simulate the DPC circuit and explore in the computer thousands of resistor combinations, looking for a distortion-free flood field image. The optimal combination found in the computer are then implemented in the laboratory, confirming the results of the simulation. In addition, we have verified that this optimized DPC preserves the pulse shape to the extent that a phoswich configuration of LYSO and GSO crystals can be read and disentangled.

Speaker: Mr Miguel Garcia Diez (Universidad Complutense de Madrid)

16 Search for Electron Capture in 176Lu with a LYSO scintillator

Naturally occurring $^{176}$Lu decays by β- decay to $^{176}$Hf with a half-life of 37.8 Gyr.
This radioactive decay provides an important isotopic clock (Lu/Hf) to date meteorites and minerals, furthermore $^{176}$Lu/$^{176}$Hf can be used as an s-process thermometer in studies of stellar nucleosynthesis.
It has been suggested that some discrepancies involving Lu/Hf age comparisons in different samples could be reconciled if $^{176}$Lu also underwent significant electron capture (EC) decay.
In particular, besides the well known β- decay to $^{176}$Hf, the $^{176}$Lu is also expected to be unstable with respect to electron capture decay to $^{176}$Yb. The Q$_{EC}$ for decay to the $^{176}$Yb ground state is 106.2 keV. Thus, EC decays to both the J$^p$ =0$^+$ ground state and the J$^p$ =2$^+$ 82 keV first excited state of $^{176}$Yb are both possible. These EC decay branches would be 7$^{th}$ and 5$^{th}$ forbidden transitions, respectively, and thus are expected to be negligibly small.
Previous searches of the $^{176}$Lu EC decay were performed by using a passive Lutetium sources and looking for the $^{176}$Yb* 82 keV gamma or the characteristic Yb X-rays in a HP-Ge detector.
Our new approach uses a LYSO crystal scintillator coupled to a PMT as an active Lutetium source, acquired in coincidence with an HP-Ge; this allows a powerful reduction of the background provided by the known $^{176}$Lu β- decay branch.
The preliminary results of the measurement on a detector prototype arranged in the INFN-TIFPA laboratory will be summarized, the upper limits to the EC branching ratio of $^{176}$Lu decay has been improved by a factor 3-20 (depending on the considered EC channel) with respect to previous measurements.

Speaker: Francesco Nozzoli (Universita degli Studi di Trento and INFN (IT))

20221025_Nozzoli_EuNPC2022.pdf

P2 Nuclear Structure, Spectroscopy, and Dynamics

17 Nuclear structure investigation at FAIR phase 0: first results from the DESPEC campaign

The HISPEC-DESPEC collaboration aims at studying the evolution of the shell structure and
exotic nuclear shapes in uncharted nuclear territory, providing spectroscopic information for the
nucleosynthesis of medium to heavy nuclei, exploiting the uniqueness of the GSI-FAIR laboratory.
In this first years after the restart of GSI, starting from early commissioning in 2019 to real
experiments in 2020-2022, the collaboration focused on stopped-beams experiments, with the aim
of providing a complete picture of the  -decay process [1,2]. The use of the FATIMA array coupled
to HPGe detectors provides, in fact, a detailed reconstruction of the decay scheme with a particular
focus on specific observables, such as levels lifetimes.
In this contribution a detailed description of the detection equipment and first results of the
campaigns, together with an outlook onto the future experimental program will be given.
References
[1] M.Rudiger et al., Nucl. Inst. and Meth. A 969 (2020) 163967.
[2] A.K.Mistry et al., Nucl. Inst. and Meth. A 1033 (2022) 166662..

Speaker: Dr Giovanna Benzoni (INFN Milano (IT))

GBenzoni.pdf

GBenzoni.pptx

18 Beta decay properties calculated with the projected generator coordinate method

Beta-decay rates are key quantities to understand both nuclear structure properties as well as the dynamics of nucleosynthesis processes. However, microscopic calculations based on the evaluation of nuclear matrix elements using eigenstates of the mother and daughter nuclei separately are scarce.
From a beyond-mean-field point of view, one of the main problems is the evaluation of the structure of nuclei with an odd number of particles because it involves the implementation of the full-blocking technique. Hence, the breaking of the time-reversal symmetry inherent to the blocking increases the complexity of the calculation.
In this contribution we will present a novel method based on the projected generator coordinate method (PGCM) to compute single-beta-decay nuclear matrix elements. This method includes the mixing of particle number and angular momentum projected intrinsic (blocked) wave functions that are used both to compute the spectra of the mother and daughter nuclei as well as the transition probabilities between the different states. We will show a first benchmark of the method by comparing B(GT) values calculated with exact diagonalizations and with the PGCM method in the sd-shell with the USD interaction.

Speaker: Tomas R. Rodriguez (Universidad Complutense de Madrid)

19 Beta-delayed $\gamma$-spectroscopy of $^{71}$Kr

$^{71}$Kr was produced through the fragmentation of a $^{78}$Kr primary beam at the RIKEN-RIBF facility in Japan, in order to have the first comprehensive study of its $\beta$-decay leading to its mirror counterpart ($^{71}$Br). The $\beta$-decay of $^{71}$Kr has a significance from the astrophysical point-of-view, as it is a waiting point of the rp-process [1]. The question of the ordering of the ground state doublet of $^{71}$Kr also remains open, with spin-parities 5/2$^{-}$ and 1/2$^{-}$ and an energy difference of 10 keV for $^{71}$Br [2].

The fragments of $^{78}$Kr were identified using standard $\Delta\text{E-B}\rho$-ToF method [3]. A double-sided silicon strip array (WAS3ABi) was used for the implant and decay station [4]. The $\gamma$-rays were measured by a surrounding HPGe cluster array (EURICA) [5].

One of the main goals of the analysis was to derive the half-life of the $\beta$-decay using independent methods to rule out systematic uncertainties. We have used three methods: 1) Bateman-fit of implant-$\beta$ time correlations, 2) exponential fit of implant-($\beta\gamma$) time correlations of verified $\gamma$-transitions, 3) exponential fit of implant-proton time correlations of $\beta$-delayed prompt proton emission.

The other goal was to build the decay-scheme of the $\beta$-decay. Level ordering and $\gamma$-transition intensities were validated using $\gamma\gamma$-coincidences and the balance of in- and outgoing $\gamma$-feeding of levels. Levels with log$ft<$ 6 have been identified and placed in the level-scheme, including 8 new levels and 26 new $\gamma$-transitions.

The probability of proton emission was also measured with a 50-fold increased precision compared to the earlier experimental value of [6]. The details of the analysis, the preliminary results and an outlook on theoretical interpretations will be presented.

Speaker: András Vitéz-Sveiczer (Institute for Nuclear Research)

EuNPC2022_71Kr_2022_10_24.pdf

20 $\beta$-delayed neutron spectroscopy of $^{85,86}$As with MONSTER

A better quantitative understanding of $\beta$-delayed neutron emission rates and spectra is relevant for nuclear structure, astrophysics, and reactor applications. The field has experienced an increased activity during the last decades [1] thanks to the advances in nuclear experimental techniques and the radioactive ion beam facilities. More accurate measurements of $\beta$-delayed neutron emission properties like the emission probability, $\beta$-feeding, and energy spectrum from individual precursors are being made with advanced neutron detectors [2, 3, 4], digital data acquisition systems [5], and high intensity ion beams [6, 7, 8, 9].

The $\beta$-delayed neutron emission in the $^{85,86}$As decays has been measured at the Ion Guide Isotope Separator On-Line (IGISOL) facility [9] of the JYFL Accelerator Laboratory of the University of Jyväskylä. The $^{85,86}$As isotopes were produced by proton-induced fission reactions in $^{238}$U, separated from the rest of the fission fragments with IGISOL, and implanted onto a tape. The complete decays have been studied with the help of a complex setup which consists of a plastic scintillator detector for the emitted $\beta$-particles and the \textbf{MO}dular \textbf{N}eutron time-of-flight \textbf{S}pectrome\textbf{TER} (MONSTER) [4, 10] for the detection of the emitted neutrons. MONSTER consists of an array of 48 cylindrical cells of 200 mm diameter and 50 mm height, filled with BC501A or EJ301 scintillating liquid. Each cell is coupled through a light guide of 31 mm thickness to a 5" diameter fast PMT. The neutron energy is determined by the time-of-flight technique, using the signals from the plastic detector and MONSTER as the start and stop signals, respectively.

In this conference, we report the results obtained from the measurement at JYFL. The $\beta$-delayed neutron energy distribution of the $^{85,86}$As $\beta$-decays has been determined by unfolding the time-of-flight spectrum with the iterative Bayesian unfolding method [11]. We also compare the results of this work to existing data [12, 13].

1. P. Dimitriou et al., Nuclear Data Sheets 173, 144-238 (2021).
2. A. Buţă et al., Nucl. Instrum. and Methods A 455, 412-423 (2000).
3. C. Matei et al., Proceedings of the 10th International Symposium on Nuclei in the
   Cosmos, 138, Proceedings of Science, 1-5 (2008).
4. A.R. Garcia et al., JINST 7, C05012 (2012).
5. D. Villamarin et al., In preparation.
6. W.F. Henning et al., GSI publication, (2001).
7. H. Okuno et al., Prog. Theor. Exp. Phys., 03C002 (2012).
8. R. Catherall et al., Nucl. Instrum. and Methods B 317, 204-207 (2013).
9. I.D. Moore et al., Nucl. Instrum. and Methods B 317, 208 (2013).
10. T. Martinez et al., Nuclear Data Sheets 120, 78 (2014).
11. G. D’Agostini, Nucl. Instrum. and Methods A 362, 487-498 (1995).
12. K.-L. Kratz et al., Nucl. Phys. A 317, 335 (1979).
13. D. Rudstam et al., Data and Nucl. Data Tables 53, 1 (1993).

Speaker: Alberto Pérez de Rada Fiol (CIEMAT)

EuNPC2022_MONSTER_As8586.pdf

21 Isomeric lifetime measurement of the neutron-rich isotope 189Ta

S. Alhomaidhi$^{\mathrm{1,2}}$, V. Werner$^{\mathrm{1,2}}$, P.-A. Söderström$^{\mathrm{1,12}}$, P. R. John$^{\mathrm{1}}$, U. Ahmed$^{\mathrm{1}}$, H. M. Albers$^{\mathrm{2}}$, C. Appleton$^{\mathrm{6}}$, T. Arıcı$^{\mathrm{2}}$, M. Armstrong$^{\mathrm{2,4}}$, A. Banerjee$^{\mathrm{2}}$, J. Benito$^{\mathrm{11}}$, A. Blazhev$^{\mathrm{4}}$, P. Boutachkov$^{\mathrm{2}}$, A. Bozo$^{\mathrm{5}}$, A. M. Bruce$^{\mathrm{10}}$, M. M. Chishti$^{\mathrm{3}}$, S. M. Collins$^{\mathrm{5}}$, T. Davinson$^{\mathrm{6}}$, T. Dickel$^{\mathrm{2}}$, A. Esmaylzadeh$^{\mathrm{4}}$, L. M. Fraile$^{\mathrm{11}}$, J. Gerl$^{\mathrm{2}}$, M. Górska$^{\mathrm{2}}$, J. Ha$^{\mathrm{9}}$, E. Haettner$^{\mathrm{2}}$, O. Hall$^{\mathrm{6}}$, H. Heggen$^{\mathrm{2}}$, N. Hubbard$^{\mathrm{1,2}}$, S. Jazrawi$^{\mathrm{3}}$, J. Jolie$^{\mathrm{4}}$, R. Kern$^{\mathrm{1}}$, L. Knafla$^{\mathrm{4}}$, I. Kojouharov$^{\mathrm{2}}$, N. Kurz$^{\mathrm{2}}$, A. K. Mistry$^{\mathrm{2}}$, J. R. Murias$^{\mathrm{11}}$, N. Pietralla$^{\mathrm{1}}$, Zs. Podolyak$^{\mathrm{3}}$, M. Polettini$^{\mathrm{7,8}}$, F. Recchia$^{\mathrm{9}}$, P. H. Regan$^{\mathrm{3}}$, J.-M. Régis$^{\mathrm{4}}$, M. Rudigier$^{\mathrm{1}}$, E. Sahin$^{\mathrm{1,2}}$, V. Sánchez-Tembleque$^{\mathrm{11}}$, H. Schaffner$^{\mathrm{2}}$, L. Sexton$^{\mathrm{6}}$, A. Sharma$^{\mathrm{2}}$, Ch. Scheidenberger$^{\mathrm{2}}$, R. Shearman$^{\mathrm{5}}$, J. M. Udías$^{\mathrm{11}}$, J. Wiederhold$^{\mathrm{1}}$, P. Woods$^{\mathrm{6}}$, A. Yaneva$^{\mathrm{2,4}}$, R. Zidarova$^{\mathrm{1}}$ on behalf of DESPEC collaboration

1 Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
2 GSI Helmholzzentrum für Schwerionenforschung GmbH, Darmstadt, Germany
3 Department of Physics, University of Surrey, Guildford, GU2 7XH, UK
4 Institut für Kernphysik, Universität zu Köln, 50937 Köln, Germany
5 National Physical Laboratory, Teddington, Middlesex TW11 0LW, UK
6 School of Physics and Astronomy, University of Edinburgh, EH9 3FD Edinburgh, UK
7 Universita degli Studi di Milano, Via Celoria 16, 20133, Milano, Italy
8 INFN, sez. di Milano, Via Celoria 16, 20133, Milano, Italy
9 Dipartimento di Fisica e Astronomia dell'Universita di Padova and INFN Padova, 35131, Padova, Italy
10 School of Computing, Engineering, and Mathematics, University of Brighton, Brighton BN2 4GJ, UK
11 Grupo de Fisica Nuclear, FAMN, Universidad Complutense, CEI Moncloa, 28040 Madrid, Spain
12 Extreme Light Infrastructure - Nuclear Physics (ELI-NP), Magurele 077126, Romania

---

In March 2021, the DEcay SPECtroscopy (DESPEC) experiment S452 was performed at GSI Helmholtzzentrum für Schwerionenforschung. The focus of the experiment was to measure the lifetimes and energies of the first exited states of neutron-rich Os, W and Hf isotopes in the A~190 mass region, in search for prolate-oblate shape transition [1]. The experimental setting, which was centered on $^{\mathrm{190}}$Ta, allowed us to investigate the single-particle structures of isomers in this region and connect their decays to the shape evolution.

The isomeric state for the nucleus of interest, $^{\mathrm{189}}$Ta, was populated by the fragmentation of $^{\mathrm{208}}$Pb primary beam impinging on $^{\mathrm{9}}$Be target [2]. The cocktail beam was separated and identified using FRagment Separator (FRS) [3] to implant the nuclei of interest in the active stopper, Advance Implantation Detector Array (AIDA). The AIDA consist of 3 Double Sided Silicon Strip Detectors (DSSSDs) [4] and located in the final focal plan of the FRS. The gamma rays from the implanted ions were detected by thirty six LaBr$_{\text{3}}$(Ce) detectors the Fast TIMing Array (FATIMA) [5] and two cluster HPGe detectors, 7 crystal each (EUROBALL), surrounding the AIDA. The LaBr$_{\text{3}}$(Ce) detectors were used for fast-timing spectroscopy, while HPGe provides precise energy information.

Data obtained in this experiment is analyzed on an event-by-event basis, for which the analysis is in progress. An overview of the DESPEC setup, the analysis procedures regarding this experiment and a preliminary result of the isomeric lifetime measurement of $^{\mathrm{189}}$Ta will be presented in the conference.

---

[1] R. F. Casten, Progress in Particle and Nuclear Physics 62, 183 (2009).
[2] T. Brock et al., Phys. Rev. C 82, 061309 (2011).
[3] S. Pietri et al., Nucl. Instrum. Meth. Phys. Res. A 261 (2007) 1079.
[4] "AIDA TDR, " [Online]. Available: https://fair-center.de/fileadmin/fair/experiments/
HISPEC_DESPEC/documents/TDR_HISPEC_DESPEC_AIDA_public.pdf
[5] "FATIMA TDR, " [Online]. Available: https://fair-center.de/fileadmin/fair/experiments/
HISPEC_DESPEC/documents/TDR_HISPEC_DESPEC_FATIMA_public.pdf

Speaker: Sultan Alhomaidhi (TU Darmstadt/ GSI)

189Ta_Isomers_EuNPC.pdf

P3 Nuclear Astrophysics

22 S-process Nuclear Reaction Rates

In stars the $\rm ^{13}C(\alpha,n)^{16}O$ and $\rm ^{22}Ne(\alpha,n)^{25}Mg$ reactions are the two main sources of neutrons for the so-called slow neutron capture process (s-process), which is the main mechanism for the stellar synthesis of heavy elements. About $\rm ^{13}C(\alpha,n)^{16}O$, in despite of many efforts in measuring its cross section at the lower energies, only high uncertainty data above the s-process Gamow window (140 keV < $\rm E_{cm}$ < 230 keV) were available, due mostly to the difficulties on suppress the natural background. Indeed, only recently the LUNA collaboration performed high precision underground measurements of the reaction cross section inside the Gamow window, improving the accuracy of its extrapolation at the lower energies. Again due to natural background, only upper limits for the $\rm ^{22}Ne(\alpha,n)^{25}Mg$ reaction cross section are currently known in the s-process Gamow window (450 keV < $\rm E_{cm}$ < 750 keV). For this, the ERC founded project SHADES (Unina/INFN) aims to perform high precision and high sensitivity measurements of the $\rm ^{22}Ne(\alpha,n)^{25}Mg$ reaction cross section down to neutron threshold. A sensitivity improvement of at least two orders of magnitude over the state of the art is expected thanks to the low natural background environment of INFN-LNGS laboratory in Italy, the high beam current of the new LUNA-MV accelerator and the Beam Induced Background events suppression performed by SHADES hybrid detectors array.
In this talk I will present the LUNA efforts to estimate nuclear reaction rates for $\rm ^{13}C(\alpha,n)^{16}O$, with a focus on R-Matrix analysis performed with the code AZURE2 to extrapolate the rates at stellar energies and the estimate of their uncertainty through Monte Carlo methods. I will also present an overview of the SHADES project to measure $\rm ^{22}Ne(\alpha,n)^{25}Mg$ in the Gamow window and the first results on the setup commissioning.

Speaker: David Rapagnani (University of Naples "Federico II")

23 The first nuclear reaction measurements on the CRYRING using the CARME chamber

Storage rings rings provide a new and unique opportunity to resolve long standing by performing nuclear reactions using stored heavy ion beams on an ultra-thin internal gas-jet target. The CRYRING storage ring, part of FAIR phase-0, is unique worldwide by allowing ion beams to be decelerated, cooled and circulated at energies of astrophysical interest. The recently installed and commissioned CRYRING Array for Reaction MEasurements (CARME) chamber utilises this novel methodology and will be used to study direct nuclear reactions at energies of astrophysical interest in addition to indirect studies of key nuclear properties with consequences for quiescent and explosive astrophysical environments.

I will present the technical capabilities of the CARME system and results of the first commissioning run. The CARME chamber was mounted on the CRYRING in September 2021. High resolution (30 keV FWHM), highly segmented (128x128 strip) Double-Sided Silicon Strip Detectors (DSSSD) were installed in the chamber and proved that XHV pressures, required for circulation of beam around the ring, could be achieved with detectors and the accompanying electrical cabling installed directly under vacuum with no pockets or windows. The detectors are capable of movement which is required to avoid un-cooled beam in the storage ring.

CARME was successfully commissioned in February 2022. This was the first use of the internal gas target, the first beam on target and first observation of nuclear reactions at the CRYRING and acts as a launch pad for the exciting physics programme ahead.

Speaker: Jordan Marsh (University of Edinburgh)

EUNPC22-JM.pptx

24 Using an active target time projection chamber to study reactions of astrophysical interest.

Active Targets are a choice in low-energy nuclear physics when luminosity and high detection efficiency are needed. When combined with a solenoid magnet, their energy dynamic range and particle identification capabilities are greatly enhanced. The Active Target Time Projection Chamber (AT-TPC) of the FRIB is one such detector, a powerful tool to investigate direct and resonant reactions where the excitation function has to be measured continuously with high precision. As an example, 22Mg(α,p) at low bombarding energies was measured. This is first direct measurement of this reaction that plays a key role for Type-I X-ray burst (XRB) light curves. In this talk I will introduce the Active Target technique and I will present the results obtained in this experiment and future possibilities.

Speaker: Saul Beceiro Novo (Universidade da Coruña)

SaulEuNPC.pdf

P5 Heavy Ion Collisions and QCD Phases

25 Hot and dense strongly interacting matter from lattice QCD - a mini review

I will give a brief overview of recent progress on the bulk thermodynamic properties of hot and dense strongly interacting matter, from first principle lattice QCD simulations. In particular, I will discuss the related topics of the equation of state, the phase diagram and fluctuations of conserved charges in the grand canonical ensemble.

Speaker: Attila Pasztor (Eötvös University)

eunpc.pdf

26 Constraining the QCD phase diagram

Lattice simulations of QCD at finite temperature are prohibited by a strong sign problem,
so that little first principles information is available on the QCD phase diagram.
However, over the last two decades, lattice as well as functional methods have collected increasingly abundant and reliable information about the phase structure of QCD
with parameters tunedd away from the physical point. In particular, the order of the QCD thermal transitioon at zero density and in the chiral limit is now settled. Taken together, these results provide increasingly stringent constraints on the location of a possible
critical point for physical QCD.

Speaker: Owe Philipsen

EuNPC22.pdf

27 Centrality dependent Lévy analysis of two-pion Bose-Einstein correlation functions at \sqrt{sNN} = 200 GeV at PHENIX.

We present the recent PHENIX preliminary data on centrality dependence of two-pion Bose-Einstein correlation functions measured in \sqrt{sNN} = 200 GeV Au+Au collisions at the Relativistic Heavy Ion Collider (RHIC). The data are well described by assuming the source to be a Lจฆvy-stable distribution. The Lévy parameters, \lambda, R, \alpha are measured in 23 bins of transverse mass (mT) for 6 centrality intervals. We observe that ฆห(mT) is constant at larger values of mT but decreases as mT decreases. The centrality dependence of this decrease is determined. The Lจฆvy scale parameter R(mT) decreases with mT and exhibits a clear centrality ordering which supports its geometrical interpretation. The Lจฆvy exponent \alpha(mT) is independent of mT in every centrality bin but shows some centrality dependence. At all centralities \alpha is significantly different from that of a Gaussian (\alpha = 2) or Cauchy (\alpha = 1) source distribution. The data are compared to Monte-Carlo simulations of resonance decay chains. In all but the most peripheral centrality class (50-60%) they are found to be inconsistent with the measurements unless a significant reduction of the in-medium mass of the \eta' meson is included. The best value of the in-medium mass is found to be consistent with the Pisarski-Wilczek limit.

Speakers: Tamas Novak (MATE Institute of Technology Karoly Robert Campus (HU)), Tamas Novak (MATE Institute of Technology Karoly Robert Campus (HU))

novak-eunpc2022_v2.pdf

novak-eunpc2022_v2.pptx

28 The road to first physics with the MPD at NICA

The Multi-Purpose Detector (MPD) is one of the two heavy-ion experiments under construction in the Nuclotron-based Ion Collider fAcility (NICA) at the Joint Institute for Nuclear Research (JINR) in Dubna, which is designed to run in the collider mode. In its initial stage of operation, planned to start at the end of 2023, the MPD will study collisions of heavy ions in the energy range $\sqrt{s_{NN}}=4-11$ GeV, starting with Bi+Bi collisions at $\sqrt{s_{NN}}=9.2$ GeV. The MPD is an international collaboration consisting of 31 institutions from 10 countries with more than 450 participants. The MPD aims to study the phase diagram of QCD matter at maximum baryon density, to determine the onset and the nature of the phase transition between the deconfined and hadronic matter and to search for the conjectured critical end point. In this talk, we describe the MPD detector and its physics program, with emphasis on the first physics measurements with Bi beams as well as the expected performance of all the detector subsystems.

Speaker: Ivonne Maldonado

EuNPC2022.pdf

P6 Hadron Structure, Spectroscopy, and Dynamics

29 Present and Future of TMDs

In the recent years, it has been realized that beyond the successful perturbative and collinear description of hard scatterings, a variety of polarization-dependent observables exists sensitive to the elusive quark-gluon interactions.
New parton distributions and fragmentation functions have been introduced that, besides the hard probe scale, explicitly depend on the parton transverse momentum at the scale of confinement (TMDs). They allow to describe the rich complexity of the hadron structure and formation, and to move towards a multi-dimensional imaging of the underlying parton correlations.
Their study promises to open a unprecedented gateway to the peculiar nature of the strong interaction. This work presents a selection of available observations, and upcoming measurements planned in particular at Jefferson Lab and at the future Electron-Ion Collider, to address the mysteries of the nucleon structure from a modern point of view.

Speakers: Marco Contalbrigo (Universita e INFN, Ferrara (IT)), Marco Contalbrigo (Dipartimento di Fisica), Marco Contalbrigo

Contalbrigo_EuNPC.pdf

30 Lambda_c semileptonic decay including new physics

We study deviations from the Standard Model in the Lambda_c to Lambda_s semileptonic decay, where lepton flavour universality violation could be observed. We consider generalised dimension-6 semileptonic c to s operators of scalar, pseudoscalar, vector, axial-vector and tensor types. We rely on lattice QCD for the hadronic transition form factors, employing heavy quark spin symmetry (HQSS) to estimate those that have not yet been determined on the lattice. Uncertainties due to the truncation of the new-physics Hamiltonian and different implementations of HQSS are carefully taken into account. As a result, we unravel the new-physics discovery potential of the Lambda_c semileptonic decay in different observables.

Speaker: Fernando Alvarado

Lambda_c_presentation.pdf

31 Neutrino-induced one-pion production revisited: the $\nu_\mu n\to\mu^- n\pi^+$ channel

Understanding single pion production reactions on free nucleons is the first step towards a correct description of these processes in nuclei, which are important for signal and background contributions in current and near future accelerator neutrino oscillation experiments. We reanalyze our previous studies of neutrino-induced one-pion production on nucleons for outgoing $\pi N$ invariant masses below 1.4 GeV, in order to get a better description of the $\nu_\mu n\to\mu^- n\pi^+$ cross section, for which current theoretical models give values significantly below data,. The $\nu_\mu n\to\mu^- n\pi^+$channel is very sensitive to the crossed $\Delta (1232)$ contribution and thus to spin 1/2 components in the Rarita-Schwinger $\Delta$ propagator. We show how these spin 1/2 components are nonpropagating and give rise to contact interactions. In this context, we point out that the discrepancy with experiment might be corrected by the addition of appropriate extra contact terms and argue that this procedure will provide a natural solution to the $\nu_\mu n\to\mu^- n\pi^+$ puzzle. To keep our model simple, in this work we propose to change the strength of the spin 1/2 components in the $\Delta$ propagator and use the $\nu_\mu n\to\mu^- n\pi^+$ data to constraint its value. With this modification, we now find a good reproduction of the $\nu_\mu n\to\mu^- n\pi^+$ cross section without affecting the good results previously obtained for the other channels. We also explore how this change in the $\Delta$ propagator affects our predictions for pion photoproduction and find also a better agreement with experiment than with the previous model.

Speaker: ELIECER HERNÁNDEZ GAJATE

hernandez.pdf

32 NP effects in $\Lambda_b\to\Lambda_c^{(∗)}$ semileptonic decays.

In the context of lepton flavor universality violation (LFUV) studies, we study different observables related to the $b\to c\tau \bar{\nu}_\tau$ semileptonic decays. These observables are expected to help in distinguishing between different NP scenarios. Since the $\tau$ lepton is very short-lived, we consider three subsequent $\tau$-decay modes, two hadronic $\pi\nu_\tau$ and $\rho\nu_\tau$ and one leptonic $\mu\bar{\nu}_\mu\nu_\tau$. This way the differential decay width can be written in terms of visible (experimentally accessible) variables of the massive particle created in the $\tau$ decay. We present numerical results for the observables that can be accessed through the visible kinematics for the $\Lambda_b\to\Lambda_c$ and the $\Lambda_b\to\Lambda_c^*(2595)$ transitions. This work is based on JHEP 10 (2021) 122, JHEP 04 (2022) 026 and arXiv:2207.10529.

Speaker: Neus Penalva Martínez (Instituto de Física Corpuscular (CSIC-UV))

EuNPC22_Neus.pdf

P9 Few-Body Systems

33 Impact of core excitations in break-up reactions with halo nuclei

Halo nuclei have been a prolific field of Nuclear Physics since its discovery together with the dawn of radioactive beam facilities. The halo is formed by one or two weakly bound nucleons orbiting around the rest of nucleons that conforms a compact core. Following this picture, halo nuclei are often treated within two- or three-body valence-core models, considering an inert core. However, the development of radioactive beam facilities are discovering new halo nuclei in regions further and further away from the stability valley. Halo nuclei formed in these regions exhibit more complex cores which will be easily excited during a nuclear reaction.

Due to this fact, a great effort has been made to incorporate the effect of core excitations in few-body reaction formalisms, such as a non-recoil extension of the Distorted Waves Born Approximation (NR-DWBA) [1], the Extended Continuum-Discretized Coupled-Channels (XCDCC) [2], and the extension of the Faddeev/AGS equations [3]. Alongside these developments, there has been a revival of models capable to include such excitations in a simple way to allow its inclusion in reaction calculations. That is the case of particle-rotor, particle-vibrator and Nilsson models. However, sometimes there is very little information to fix the corresponding parameters of these models or the structure of the core does not fit into a rotor or a vibrator. To overcome this drawback, we will show how to construct a semi-microscopic folding potential based on core transition densities [4]. This model was tested on 11Be nucleus showing a notable predictive power, which we applied to 19C.

In this contribution we will show how core excitations can contribute and even dominate resonant break-up of halo nuclei like 19C by analyzing 19C(p,p') experimental data from Y. Satou et al. [5,6]. We will also use XCDCC to study Coulomb break-up of 11Be in order to extract information about its Dipole Electric Transition Probability, B(E1). In this case, two different sets of 11Be on 208Pb data [7,8] led to apparently incompatible B(E1) distributions. We will discuss a recently proposed procedure to extract the B(E1) with the help of a modified version of XCDCC which has been able to obtain compatible B(E1) from both data, giving an end to this long-standing discrepancy [9]

[1] A. M. Moro and R. Crespo, Phys. Rev. C 85, 054613 (2012)
[2] N. C. Summers, F. M. Nunes, and I. J. Thompson, Phys. Rev. C 74, 014606 (2006)
[3] A. Deltuva, Phys. Rev. C 88, 011601(R)(2013)
[4] J. A. Lay, A. M. Moro, J. M. Arias, and Y. Kanada-En'yo, Phys. Rev. C 89, 014333 (2014)
[5] Y. Satou et al., Phys. Lett. B 660, 320 (2008)
[6] J. A. Lay, R. de Diego, R. Crespo, A. M. Moro, J. M. Arias, and R. C. Johnson, Phys. Rev. C 94, 021602(R) (2016)
[7] N. Fukuda, et al., Phys. Rev. C 70, 054606 (2004)
[8] R. Palit, et al., Phys. Rev. C 68, 034318 (2003)
[9] A.M.Moro, J.A.Lay, and J.Gómez Camacho, Phys. Lett. B 811, 135959 (2020)

Speaker: José Antonio Lay Valera (Dpto. de Física Atómica, Molecular y Nuclear, Universidad de Sevilla)

EuNPC_22_Lay.pdf

34 Dineutron correlations in knockout reactions with Borromean halo nuclei

A key element to explain the binding of loosely bound Borromean halo nuclei is the correlation between the halo neutrons [1,2]. The characterization of the dineutron correlation, understood as a spatially localized $n$-$n$ pair, is therefore an important step in the description of the neutron dripline. Various experimental techniques have been used in recent years to probe these correlations, including Coulomb dissociation, neutron knockout and quasifree neutron removal [3-5]. Theoretically, the localization of the pair at the low-density surface of neutron-rich nuclei has been suggested to appear as a universal feature for these systems [6,7], and can be linked to the admixture of different-parity states [8].

I will present recent results for various two-neutron halo nuclei explored via $(p,pn)$ neutron knockout. We will study the $n$-$n$ correlations focusing on the opening angle as a function of the intrinsic neutron momentum. Our approach is based on a $\text{core}+n+n$ three-body model for the structure and a quasifree sudden model for the reaction [9]. For $^{11}$Li, $^{14}$Be and $^{17}$B, calculations will be compared to recent RIKEN data [5,10], supporting the aforementioned universality. The sensitivity to small opposite-parity admixtures and to absorption effects, as well as the role played by the core in the observation of such correlations, will be discussed. These results pave the path for future studies on $n$-$n$ correlations in heavier dripline nuclei.

[1] M. V. Zhukov et al., Phys. Rep. 231, 151 (1993).
[2] K. Hagino and H. Sagawa, Phys. Rev. C 72, 044321 (2005).
[3] Nakamura et al., Phys. Rev. Lett. 96, 252502 (2006).
[4] H. Simon et al., Phys. Rev. Lett. 83, 496 (1999).
[5] Y. Kubota et al., Phys. Rev. Lett. 125, 252501 (2020).
[6] M. Matsuo, Phys. Rev. C 73, 044309 (2006).
[7] K. Hagino, H. Sagawa, J. Carbonell and P. Schuck, Phys. Rev. Lett. 99, 022506 (2007).
[8] F. Catara, A. Insolia, E. Maglione and A. Vitturi, Phys. Rev. C 29, 1091 (1984)
[9] J. Casal and M. Gómez-Ramos, Phys. Rev. C 104, 024618 (2021).
[10] A. Corsi et al., submitted.

Speaker: Jesús Casal (University of Seville)

jcasal_eunpc2022.pdf

35 INVESTIGATION OF THE 7,6H STATES IN 8He+d INTERACTION

Investigation of the 6H and 7H isotopes, has long history going up to these days. These the most neutron rich systems with the biggest ratio of mass-over charge, which makes these systems attractive to study. The high intensity 8He secondary beam with energy 26 AMeV, produced at the recently commissioned ACCULINNA-2 fragment separator [1], was used for the population of the systems of interest in the 8He+d interaction. The detection the low-energy recoils 4He and 3He made with good energy and angular resolution allowed us to reconstruct the missing-mass spectra of 6H and 7H populated in the 2H(8He,4He)6H and 2H(8He,3He)7H reactions. The applied experimental techniques, the results of the data analysis and simulations will be presented in our report. The ground state 1/2+ at 2.2(5) MeV of 7H and (possibly) the 5/2+ -3/2+ doublet of the first excited states, located in the energy range 5.5-7.5 MeV, were populated in the proton transfer reaction from the 8He beam on deuterium cryogenic gas target [2,3]. As compared to previous works, experiment [2,3] features the reliable channel identification, better energy resolution, and additional support from the obtained angular and energy distributions. The obtained results presumably resolve the problem of search for the 7H ground state which was not successful for more than 40 years. The 6H studies were a “satellite activity” of the 7H investigation [4]. The obtained results allowed us to observe a resonant state in 6H at 6.8 MeV above the 3H+3n decay threshold and to obtain an indication on a resonant state at 4.5 MeV, which is a realistic candidate for the 6H ground state. In addition, the measured momentum distributions of the 3H fragments, represented in the 6H rest frame, provided evidence for an extremely strong “dineutron-type” correlation occurring in the decay of the 5H ground state. All together, the obtained data on the low-energy spectra of 6H and 7H systems shed light on the spectroscopy of these exotic systems and decay mechanisms of their ground and exited states.
References:
[1] A.S. Fomichev, L.V. Grigorenko, S.A. Krupko, S.V. Stepantsov, G. M. Ter-Akopian, The EPJ A 54 (2018) 97.
[2] A.A. Bezbakh et al., Phys. Rev. Lett. 124 (2020) 022502.
[3] I.A. Muzalevskii et al., Phys. Rev. C 103 (2021) 044313.
[4] E.Yu. Nikolskii et al., Phys. Rev. C 105 (2022), 064605].

Speaker: Ivan Muzalevskii (Joint Institute for Nuclear Research)

eunpc2022.pdf

36 Differential Cross Section for Proton Induced Deuteron Breakup at 108 MeV

Studies of few-nucleon systems form the basis for understanding nuclear interactions and properties of nuclei. The very accurate theoretical calculations for three-nucleon systems should be confronted with a rich set of precise experimental data.
For this purpose, the BINA (Big Instrument for Nuclear-polarization Analysis) detection system has been installed at CCB (Cyclotron Center Bronowice) [1]. The BINA setup is designed to study the elastic and breakup reactions at intermediate energies. It consists of the liquid target facility and the low threshold detector covering nearly 4π solid angle, enabling studies of almost full phase space of these reactions [2,3].
The data analysis and results of the first experimental run of proton-induced deuteron breakup at a beam energy of 108 MeV will be presented. The data are normalized to the known cross section for proton-deuteron elastic scattering [4]. Differential cross section determined for a set of over 200 kinematic configurations of proton pairs registered in the forward part of BINA will be compared to state-of-the-art theoretical calculations to study the role of the Three Nucleon Force, Coulomb, and relativistic effects.

[1] A. Łobejko et al., Acta Phys. Pol. B. 50, 3, p.361-366 (2019).
[2] St. Kistryn, E. Stephan, J. Phys. G: Nucl. Part. Phys. 40, 063101 (2013).
[3] A. Ramazani-Moghaddam-Arani, et al., Phys. Rev. C 78, 014006 (2008).
[4] K. Ermisch, et al., Phys. Rev. C 68, 051001 (2005).

Speaker: Ms Angelina Łobejko (University of Silesia)

Lobejko_Santiago_EUNPC22.pdf

16:45 Coffee Break

P1 Accelerators and Instrumentation

37 Standardization of $^{18}F$ using new portable $4\pi\beta(LS)-\gamma$ coincidence detection system at ENEA-INMRI

This project concerned on the development at ENEA-INMRI of new in-situ $4\pi\beta(LS)-\gamma$ coincidence detection system for activity measurement of the short half-lived radionuclides used in Nuclear Medicine. The hardware of the new portable $4\pi\beta(LS)-\gamma$ coincidence detection system was implemented at ENEA-INMRI, in collaboration with Catania University and INFN, by adding a gamma channel on the existing TDCR portable detector available at ENEA-INMRI. A new data analysis software was developed at CAEN, independently from an existing one elaborated at ENEA-INMRI, in order to analyze the data recorded in list-mode by the new detector equipped with the CAEN desktop digitizer DT5720. The activity for short half-life radionuclides used in nuclear medicine can be then computed. Two primary activity measurement - TDCR and $4\pi\beta(LS)-\gamma$ coincidence - methods were then used to determine the activity of $^{18}F$ at ENEA-INMRI. The TDCR parameter is measured for $^{18}F$ standard solution using both CAEN and ENEA-INMRI data analysis software.

Speaker: Farmesk Abubaker (Istituto Nazionale di Fisica Nucleare, Catania university)

P2 Nuclear Structure, Spectroscopy, and Dynamics

38 Constraining Neutron-Star Matter with Microscopic and Macroscopic Collisions

Interpreting high-energy, astrophysical phenomena, such as supernova explosions or neutron-star collisions, requires a robust understanding of matter at supranuclear densities. However, our knowledge about dense matter explored in the cores of neutron stars remains limited. Fortunately, dense matter is not only probed in astrophysical observations, but also in terrestrial heavy-ion collision experiments. In this work, we use Bayesian inference to combine data from astrophysical multimessenger observations of neutron stars, such as gravitational waves, and from heavy-ion collisions of gold nuclei at relativistic energies with microscopic nuclear theory calculations to improve our understanding of dense matter. We find that the inclusion of heavy-ion collision data indicates an increase in the pressure in dense matter relative to previous analyses, shifting neutron-star radii towards larger values, consistent with recent NICER observations. Our findings show that constraints from heavy-ion collision experiments show a remarkable consistency with multi-messenger observations and provide complementary information on nuclear matter at intermediate densities. This work combines nuclear theory, nuclear experiment, and astrophysical observations, and shows how joint analyses can shed light on the properties of neutron-rich supranuclear matter over the density range probed in neutron stars.

Speaker: Arnaud Le Fèvre

39 Quarteting in N=Z nuclei

The phenomenon of quarteting in even-even $N=Z$ nuclei has a
long history in nuclear structure [1]. In spite of that, several unexplored and yet interesting aspects of this phenomenon have come to light only in recent years. In Ref. [2], we have evidenced on analytic grounds the key role played by the isovector pairing in the phenomenon of nuclear quarteting. We have indeed shown that $\alpha$-like quartets, i.e., correlated four-body structures made by two protons and two neutrons, do represent the distinctive feature of the exact eigenstates of this Hamiltonian in $N=Z$ even-even systems. But how do quartets evolve in the presence of a general Hamiltonian?
I will provide a description of deformed $N=Z$ nuclei in the
$sd$ and $pf$ shells in a formalism of $\alpha$-like quartets.
I will show how these quartets can be built by resorting to
the use of proper intrinsic states and I will perform configuration-interaction calculations in spaces built with these quartets.[3]
As a peculiarity of this approach, which improves a technique
employed in previous works [4,5], it will be shown
that the spectra of these nuclei can be organized in bands
associated with the various intrinsic states built in terms of
quartets. It will also be shown that the same bands simply
result from the angular momentum projection of these intrinsic states.
Comparisons with experiment and shell model results will be provided.

[1] A. Arima, V. Gillet, and J. Ginocchio, Phys. Rev. Lett. 25 (1970) 1043.
[2] M. Sambataro and N. Sandulescu, J. Phys. G.: Nucl. Part. Phys. 47 (2020) 045112.
[3] M. Sambataro and N. Sandulescu, Phys. Lett. B 827 (2022) 136987.
[4] M. Sambataro and N. Sandulescu, Phys. Rev. Lett. 115 (2015) 112501.
[5] M. Sambataro and N. Sandulescu, Phys. Rev. C 91 (2015) 064318.

Speaker: Michelangelo Sambataro

P3 Nuclear Astrophysics

40 A new experimental setup to measure the astrophysical 15O(α,γ)19Ne reaction rate in inverse kinematics

The process that drives nucleosynthesis in x-ray bursts is known to be the rp-process, however questions still remain regarding the mechanism through which breakout from the HCNO cycle into the rp-process occurs. It has been suggested that breakout may occur via the $^{15}$O(α,γ)$^{19}$Ne reaction [1]. Hydrodynamic simulations of x-ray bursts have also shown that the rate of this reaction has a significant impact on both the light curve and final isotopic abundances [2]. Consequentially, measuring this reaction rate represents a key challenge for explosive nuclear astrophysics. It has been shown that the reaction rate is dominated by a 3/2+ excited state at 4.033 MeV in $^{19}$Ne [3]. For the contribution from this state to be determined, the alpha branching ratio needs to be measured precisely. However, this has proved extremely challenging due to how small the alpha branching ratio is ($B_{𝛼}$~$10^{−4}$ [4]).

It has been shown that the $^{21}$Ne($p$,$t$)$^{19}$Ne reaction preferentially populates the 4.033-MeV excited state [5,6], hence this reaction was chosen to study the states in $^{19}$Ne. This experiment was conducted at the Cyclotron Institute, Texas A&M. A 840-MeV, $^{21}$Ne beam was impinged onto a CH$_{2}$ target and reaction tritons were detected in a silicon telescope. The recoiling heavy ions then entered the MDM spectrometer and were detected in coincidence with a new focal plane detector, consisting of two PPACs and a phoswich.

Presented here are preliminary results from the full setup experiment, as well as a test experiment of the new focal plane detector. Both the focal plane detector and Si telescope show good particle identification. This allows for the detection of both $^{15}$O-$t$ and $^{19}$Ne-$t$ coincidences, and hence, the all-important alpha branching ratio of the 4.033-MeV state in $^{19}$Ne to be measured.

[1] M. Wiescher, J. Görres, H. Schatz, J. Phys. G 25, R133 (1999)
[2] R. H. Cyburt, et al, The Astrophys. J. 830, 55 (2016)
[3] K. Langanke, et al., The Astrophys. J. 301, 629 (1986)
[4] W. P. Tan, et al., Phys. Rev. Lett. 98, 24503 (2007)
[5] B. Davids, et al., Phys. Rev. C 67, 065808 (2003)
[6] H. T. Fortune, et al., Phys. Rev. C 18, 1563 (1978)

Speaker: Mr Ben Reed (University of Surrey)

BenReed_EuNPC_21Nept.pdf

41 Search for Supernova R-process actinides in fossilized reservoirs

Even though GW170817 and the associated kilonova from a neutron-star merger were detected in August 2017, the possible sites of r-process elements remain an open question in nuclear astrophysics, including special kinds of core-collapse supernovae (CCSNe). A well-known supernova-produced 60Fe radioisotope has been found in several terrestrial reservoirs proving that material from the ejecta of a nearby supernova arrived on earth in the last several millions of years [1]. If live r-process isotopes were to be found in temporal coincidence with the 60Fe peak, it would provide strong evidence to the r-process occurring in CCSNe. The radioisotope 244Pu has been chosen, as it is an r-process only isotope and has a very long half-live, providing the same conditions as for 60Fe. Unfortunately, it is much less abundant than even 60Fe, and therefore a highly concentrated reservoir must be found. Candidates for this type of investigations were found in Atacama Desert, Chile, and Turkana Basin.
A great challenge that arises during the 244Pu investigations is the inherent anthropogenic contamination with Plutonium isotopes released during the atmospheric nuclear weapon tests. The AMS (Accelerator Mass Spectrometry) measurements and sample preparation were carried out using the 1MV Tandetron Accelerator installed at the RoAMS Laboratory at IFIN-HH, Romania [2, 3].
Anthropogenic plutonium results obtained while investigating fossils from Turkana Basin and Atacama Desert will be presented along with data for certified reference materials and data on interstellar Pu-244.

Acknowledgements: This research was supported by the Collaborative Research Center SFB1258 of the Deutsche Forschungsgemeinschaft (SFB1258), Romanian Government Programme through the National Programme for Installations of National Interest (IOSIN). We are grateful to Dr. Livius Trache, Dr. Gihan Velisa, Dr. Mihai Straticiuc and Dr. Lucio Gialanella for their unconditional institutional support.

[1] Ludwig, P. et al. PNAS (113), 2016, 9232–9237.
[2] Pacesila D. G. et al. U.P.B. Sci. Bull. (82), 2020, 241-250.
[3] Stanciu I. et al. NIM B (529), 2022, 1-6.

Speaker: Stanciu Iuliana (IFIN-HH, Romania; TUM, Germany)

42 Phase Transitions under Strong Magnetic Fields in Neutron Stars

A comprehensive study is carried on the impact of strong magnetic fields on the deconfinement phase transition that is anticipated to occur inside massive neutron stars. The basic but effective Vector-Enhanced Bag model (vBag) is used to analyse quark matter, while the very general density-dependent relativistic mean-field (DD-RMF) model is utilised to study hadronic matter. The matter equation of state and the general relativity solutions, which also fulfill Maxwell's equations, are modified when taking magnetic-field effects into account. We observe that the maximum mass, canonical-mass radius, and dimensionless tidal deformability of stars computed using spherically-symmetric TOV equations and axisymmetric solutions obtained through the LORENE library differ significantly for large values of magnetic dipole moment. The discrepancies depend on the stellar mass being studied, as well as the stiffness of the equation of state. This clearly indicates that, contrary to what was previously believed in the literature, the matter composition and interactions determine the magnetic field thresholds for the correct assumption of isotropic stars and the appropriate application of TOV equations.

References
[1] I. A. Rather, Asloob A. Rather, V. Dexheimer, Ilidio Lopes, A. A.
Usmani, and S. K. Patra, arXiv:2209.06016[nucl-th].
[2] I. A. Rather, A. A. Usmani, and S. K. Patra, J. Phys. G 48, 085201
(2021).
[3] I. A. Rather, U. Rahaman, M. Imran, H. C. Das, A. A. Usmani, and S.
K. Patra, Phys. Rev. C 103, 055814 (2021).
[4] I. A. Rather, U. Rahaman, V. Dexheimer, A. A. Usmani, and S. K.
Patra, Astrophys. J. 917, 46 (2021).

Speaker: Dr Ishfaq Ahmad Rather (Centro de Astrofisica e Gravitacao-CENTRA, Instituto Superior Tecnico-IST, Universidade de Lisboa-UL, Av. Rovisco Pais, 1049-001 Lisboa, Portugal)

43 Contribution of meson exchange currents to the electromagnetic responses within a relativistic mean-field model

An unprecedented activity has been unleashed in recent years to determine neutrino properties and their interactions. It has been firmly established that neutrinos oscillate and hence are massive particles. Some of the oscillation parameters, such as the neutrino mixing angles, have been measured with some precision, but other properties remain to be determined, such as their masses or the phase that quantifies the possible charge-parity violation. These are some of the goals of the new generation of accelerator-based neutrino oscillation experiments NOvA, DUNE and HyperKamiokande, with which neutrino physics enters a new 'Precision Era' [1].

The fact that all neutrino oscillation experiments use complex nuclei as target material in the detectors, for example mineral oils, water or liquid argon, complicates the analysis of the results since nuclear effects must be considered. In the energy region covered by the neutrino oscillation experiments, the neutrino-nucleus scattering cross section is not very precisely known, so that it is currently one of the largest contributions to the error [2]. This is what makes the study of neutrino-nucleus interactions a hot topic and brings theoretical nuclear physics to the stage.

Among all the reaction mechanisms that take place in neutrino experiments, we focus on the quasielastic channel (QE), where the scattering off a bound nucleon which is knocked out from the nucleus occurs. This process is studied within a realistic nuclear framework, using a state of the art relativistic mean-field based model for the description of the nuclear dynamics and final state interactions within a quantum mechanical framework (see [3] and references there in). Residual interactions between the bound nucleons through pion exchange are also included. We extend the usual treatment of QE scattering, based on a one-body current operator, by incorporating a two-body meson-exchange current (MEC) one. In this work, MEC include the dominant Delta-resonance mechanism (excitation of the $\Delta$(1232) resonance and its subsequent decay into $N\pi$) and the background contributions deduced from the chiral perturbation theory Lagrangian of the pion-nucleon system [4].

The connection of electron scattering experiments with neutrino scattering allows to scrutiny the available theoretical models by a first comparison to electron scattering data. Then, in our work [5], we compare our calculation of the electromagnetic responses of the $^{12}$C nucleus with the available experimental data. We find that the effect of the two-body currents is only significant in the transverse channel, where the response is increased up to a 34%, leading to an improved description of the data compared to the one-body case. The key contribution of this work is the incorporation of the two-body meson exchange current contribution. The relativistic and quantum mechanical treatment of the process allows its application to heavier nuclei. Therefore, after the success of the model in the scrutiny against $^{12}$C electron scattering data, it is in the process of being applied to $^{40}$Ca and $^{40}$Ar.

[1] L. Alvarez-Ruso et al., Progress in Particle and Nuclear Physics 100, 1-68 (2018).
[2] K. Abe et al. (T2K Collaboration), arXiv:1607.08004 (2016).
[3] R. González-Jiménez et al. Phys. Rev. D 97, 013004 (2018).
[4] S. Scherer and M. R. Schindler, Quantum Chromodynamics and Chiral Symmetry in A Primer for Chiral Perturbation Theory. Lecture Notes in Physics, 830. Springer, Berlin, Heidelberg (2011).
[5] T. Franco-Munoz et al., arXiv:2203.09996 (2022).

Speaker: Tania Franco Muñoz

EUNPC22-TFranco.pdf

EUNPC22-TFranco.pptx

P6 Hadron Structure, Spectroscopy, and Dynamics

44 Hadron Spectroscopy with GlueX, COMPASS and LHCb

I'll review the recent works by the Joint Physics Analysis Center (JPAC) concerning the experimental extraction of properties of exotic hadron candidates.

Speaker: Vincent Mathieu (University of Barcelona)

EuNPC_Oct22.pdf

45 Even parity open charm mesons

Since 2003 many new hadrons, including the lowest-lying positive-parity charm-strange mesons D∗s0(2317) and Ds1(2460), have been observed that do not conform with quark-model expectations. We discuss how various puzzles in the charm-meson spectrum find a natural resolution if the SU(3) multiplets for the lightest scalar and axial-vector states, among them the D∗s0(2317) and the Ds1(2460), owe their existence to the nonperturbative dynamics of Goldstone-boson (P) scattering off D(s) and D∗(s) mesons. Most importantly the ordering of the lightest strange and nonstrange scalars becomes natural. We demonstrate for the first time that this mechanism is strongly supported by the recent high quality data on the B--> Dbar PP provided by the LHCb experiment. This implies that the lowest quark-model positive-parity charm mesons, together with their bottom counterparts, if realized in nature, do not form the ground-state multiplet. This is similar to the pattern that has been established for the scalar mesons made from light up, down, and strange quarks, where the lowest multiplet is considered to be made of states not described by the quark model. In a broader view, the hadron spectrum must be viewed as more than a collection of quark-model states.

Speaker: Dr Juan M Nieves (IFIC (CSIC-UV))

Nieves-STRONG.pdf

46 Spectrum and decays of the light $1^{-+}$ hybrid nonet

The nonrelativistic quark models predict the existence of one light hybrid nonet in the mass range $1.7-2.2$ GeV. As a validation of this prediction, the PDG lists an isovector state dubbed $\pi_1(1600)$ with quantum numbers $1^{-+}$. However, the observation of two such isovector with closely lying masses - $\pi_1(1400)$ and $\pi_1(1600)$ raised curiosity in the community, in part because of the complementarity of the decay channels. It is now believed that the two isovector are in fact the same and possible background effects distort the measurements in the $\eta\pi$ channel leading to a lower mass. An addition to this nonet was recently observed by the BESIII collaboration in the $J/\psi\to\gamma\eta\eta^\prime$ decays. The BESIII reported an isoscalar resonance, dubbed the $\eta_1(1855)$ having quantum numbers $1^{-+}$ with a mass of $1855\pm 9^{+6}_{-1}$ MeV and a width of $188\pm 18 ^{+3}_{-8}$ MeV. Here I report the results of our recent analysis of the nonet comprising these states.

Speaker: Vanamali Shastry (Jan Kochanowski University)

Hybrid_EuNPC_Shastry.pdf

47 Experimental access to the three-body forces between hadrons with ALICE.

Measurements of correlations between particle pairs with low relative momentum via femtoscopy in pp collisions have been recently demonstrated to be very sensitive to the effects of the final-state strong interaction. Such studies face now a new challenge with the extension for the first time to three-body systems. The presented results are obtained using high-multiplicity pp collisions at $\sqrt{s}$ = 13 TeV recorded by ALICE at the LHC.

The first measurement of the genuine three-body effects obtained from p–p–p, p–p–$\Lambda$, p–p–K$^+$ and p–p–K$^-$ correlation functions are obtained by utilising the formalism of the three-particle cumulants. Such measurements provide information on the genuine three-particle interaction and constitute important inputs for the calculation of the equation of state of neutron stars and the formation of kaonic nuclei.

In the studies of the strong interaction among hadrons, ALICE has flared out its femtoscopic studies to nuclei with the measurement of the proton-deuteron correlation function. The data that cannot be reproduced by simple two-body calculations considering p-d scattering parameters, and the necessity of using full three-body calculations is demonstrated. The obtained results bring also valuable information on the mechanism of formation of light nuclei in hadron-hadron collisions.

Speaker: Oton Vazquez Doce (INFN e Laboratori Nazionali di Frascati (IT))

EuNPC2022_Santiago.pdf

P7 Fundamental Symmetries and Interactions

48 Pulsed Production of Antihydrogen in AEgIS

Low-temperature antihydrogen atoms are an effective tool to probe the validity of the fundamental laws of Physics, for example the Weak Equivalence Principle (WEP) for antimatter, and -generally speaking- it is rather intuitive that colder atoms will increase the level of precision.

After the first production of cold antihydrogen in 2002 [1], experimental efforts have progressed substantially, with really competitive results already reached by adapting to cold antiatoms some well-known techniques previously developed for ordinary atoms. Unfortunately, the number of antihydrogen atoms that can be produced in dedicated experiments is many orders of magnitude smaller than of hydrogen atoms, so the development of novel techniques to enhance the production of antihydrogen with well defined (and possibly controlled) conditions is essential to improve the sensitivity.

We present here some experimental results achieved by the AEgIS Collaboration (based at the CERN AD - Antiproton Decelerator) on the production of antihydrogen in a pulsed mode where the production time of 90\% of atoms is known with an uncertainty of $\sim250$ ns [2]. The pulsed antihydrogen source is generated by the charge-exchange reaction between Rydberg positronium (produced via the implantation of a pulsed positron beam into a mesoporous silica target, and excited by two laser pulses) and antiprotons (trapped, cooled and manipulated in usual Penning-Malmberg traps):
$$ \bar{ p}+Ps^* \rightarrow \bar{H}^* + e^- $$ where Rydberg positronium atoms, in turn, are produced through the implantation of a pulsed positron beam into a mesoporous silica target, and are excited by two subsequent laser pulses, the first to $n=3$, the second to the needed Rydberg level.

The pulsed production (which is a major milestone for AEgIS) makes it possible to select the antihydrogen axial temperature and opens the door for the tuning of the antihydrogen Rydberg states, their de-excitation by pulsed lasers and the manipulation through electric field gradients.

In this talk, we present the results achieved by AEgIS before the Long Shutdown 2 (LS2) as well as the ongoing improvements to the system, aimed at exploiting the lower energy and more intense antiproton beam from ELENA.

[1] M.Amoretti et al., Nature 419, 456 (2002)

[2] C.Amsler et al., Commun Phys 4, 19 (2021)

Speaker: Nicola Zurlo (Universita di Brescia (IT))

EUNPC 2022 Santiago de Compostela v2.pdf

49 Search for the electric dipole moment of charged particles using storage rings

The search for Electric Dipole Moments (EDMs) of elementary particles is a powerful tool to probe physics beyond the Standard Model (SM) of Particle Physics. Since a permanent EDM violates $CP$ symmetry, an EDM measurement of a fundamental particle is a potential source of $CP$-violation that could, e.g., explain the matter-antimatter asymmetry in the universe. Moreover, a rotating polarized beam used in EDM searches is sensitive to oscillating EDM caused by axions or axion-like particles (ALPs), the candidates for the dark matter.
Storage rings make it possible to measure EDMs of charged particles by observing the effect of the EDM on the particle's spin motion in the ring. The Cooler Synchrotron COSY at the Forschungszentrum Jülich provides polarized protons and deuterons with momenta up to 3.7 GeV/s, which is an ideal testing ground and starting point for such an experimental program. The analysis of the first direct (precursor) measurement of the deuteron EDM in COSY is currently ongoing. Due to the complexity of storage rings, this study requires demanding precision in measurements and a thorough understanding of systematics. Beyond that, the design report of the prototype EDM storage ring is the next milestone of the JEDI (Jülich Electric Dipole moment Investigations) research program.
In this talk, I will present the current status of the JEDI program for the measurement of proton and deuteron EDMs, discuss the various technical developments, and show recent results. In particular, I will present a first result of our oscillation EDM measurement with polarized deuteron beams at COSY and its impact for Dark Matter searches.

Speaker: Vera Shmakova

shmakova_EUNPC.pdf

50 Unprecedented precision studies of multi-strangeness hadronic interactions with ALICE at the LHC

Understanding the dynamics of hadrons with strange quark content is crucial to solve fundamental aspects of QCD as well as for the implications on the structure of dense stellar objects, such as neutron stars. However, the current theoretical description of the interaction among hadrons with strangeness is strongly affected by the scarce statistics collected in traditional scattering experiments and by the limited data availability for hypernuclei. These limitations are particularly relevant for the study of dense nuclear matter.

In the past several years the use of correlation techniques, applied to particle pairs produced in high-energy collider experiments, have been proven capable of complementing and expanding the knowledge of hadronic interactions, especially in the strangeness sector. The present contribution provides an overview of the main milestones reached by the ALICE Collaboration using the femtoscopy technique in pp collisions at $\sqrt{s} = 13$ TeV. In particular, the latest results on the study of the interactions in four different strangeness systems, namely p-$\Lambda$ ($S=-1$), p-$\Xi^-$ ($S=-2$), $\Lambda$-$\Xi^-$ and p-$\Omega^-$ ($S=-3$) will be presented and their interpretation in the context of the available theoretical predictions will be discussed.

Speaker: Raffaele Del Grande (Technische Universitaet Muenchen (DE))

Talk_EuNPC2022_DelGrande_v1.pdf

Tapas Tour

Wednesday 26 October

Plenary Talks

51 Status of the search for cosmic-ray origins: a multimessenger view

The quest for finding the origins of cosmic rays has been going on for many decades. Cosmic rays as charged particles react to cosmic magnetic fields and therefore travel in diffusive motion through the Universe. Their imprint on Earth therefore has little information on their original direction so that finding the sources of cosmic rays is a major challenge and the question of their origins one of the leading questions in physics and astrophysics. To solve this riddle, a multimessenger approach is used. Cosmic-ray interactions in the sources lead to the production of particle showers, from which gamma-rays and neutrinos are observable on Earth. As these travel on straight paths through the Universe, these messengers can be used to further unravel the cosmic-ray origins. One messenger alone is never enough - high-energy photons are also produced by electrons via bremsstrahlung or inverse Compton scattering. High-energy neutrinos are very difficult to detect. Nevertheless, the newest generation of detectors, concerning cosmic rays themselves, high-energy gamma-rays, and neutrinos, are so advanced now that it is possible to combine the different pieces of information to deduce first evidence of where cosmic rays come from.

In this talk, the current state of the art will be reviewed from this multimessenger perspective. In particular, it will be shown how theoretical results are combined with multimessenger data in order to pinpoint the sources of cosmic rays.

Speaker: Julia Tjus

52 Neutrino oscillation anomalies

I give an overview of the several anomalies appearing in neutrino oscillation experiments. I will briefly discuss the LSND and MiniBooNE anomalies and the recent results from the MicroBooNE experiment before turning, in the main part of the talk, to the reactor antineutrino anomaly and the Gallium anomaly. I will discuss these two anomalies in some detail and, in particular, compare their explanation due to neutrino oscillations in presence of a light sterile neutrino among each other and also with the bounds from the analyses of reactor spectral ratio data, β-decay data, and solar neutrino data.

Speaker: Christoph Andreas Ternes (INFN, Sezione di Torino)

EuNPC_ternes.pdf

EPS Young Minds Project: Roundtable

11:25 Coffee Break

EPS Young Minds Project: Workshop

13:40 Lunch Break

P1 Accelerators and Instrumentation

53 The ISOLDE Solenoidal Spectrometer

One of the main limitations when performing nuclear reactions in inverse kinematics is the so-called kinematic compression. This effect is a consequence of the large centre-of-mass velocity of the scattering system, which greatly diminishes the energy resolution for a given laboratory-frame. The most successful way to suppress this effect is the use of intense magnetic fields, which avoids the complication of determining the energy of the outgoing ion as a function of the longitudinal velocity component. The outgoing ions are transported in an homogenous magnetic field parallel to the beam axis. The reaction products describe helical trajectories returning to the magnetic axis after one cyclotron period, where a detector array records their energy and position. By knowing the field intensity, all the needed observables can be extracted in order to resolve the nuclear reaction.

This is the approach followed by the new ISOLDE Solenoidal Spectrometer (ISS). ISS is installed at HIE-ISOLDE, CERN, where it can received a wide range exotic isotope beams produced at ISOLDE and reaccelerated up to 10 MeV/A. Inside the superconducting magnet, ISS can install a Si array and a $\Delta$E-E telescope, as well as a number of ancillary detectors. In this talk, this newly commissioned setup will be described and some of its first experiments preformed will be discussed.

Speaker: Bruno Olaizola (CERN)

Olaizola_ISS_2022.pdf

Olaizola_ISS_2022.pptx

54 The Measurement of Alpha Neutron Yields and spectra (MANY) project: comissioning measurement of the 27Al(α,n)30P thick target yields at CMAM using miniBELEN and LaBr3 scintillators.

(α,xn) reactions play an important role in a wide range of applications such as nuclear astrophysics, neutron-induced background in underground laboratories, fission and fusion reactors and non-destructive assays for non-proliferation and spent fuel management applications. However, most of the currently available experimental data was measured decades ago. The data is incomplete and/or present large discrepancies not compatible with the declared uncertainties. Therefore, new measurements addressing the actual needs are required [1].
The MANY collaboration is a coordinated effort by several Spanish research groups aiming to carry out measurements of (α,xn) production yields, reaction cross-sections and neutron energy spectra. The α-beams are produced by the accelerator facilities at CMAM (Madrid, Spain) [2] and CNA (Sevilla, Spain) [3]. The measurements are carried out by using the new miniBELEN detector [4], a 4π long counter with a nearly flat response up to 10 MeV based on the use of 3He-filled neutron proportional counters embedded in a modular high-density polyethylene moderator, the MONSTER array [5], a time-of-flight neutron spectrometer based on the BC501/EJ301 liquid scintillation modules, and a fast-timing array of LaBr3(Ce) scintillation detectors of the FATIMA type [6] which provides gamma detection with angular resolution capabilities.
In this work we report the first results from the comissioning experiment carried out in 2021. In particular, we present and discuss the measurement of the well-known 27Al(α,n)30P thick target production yields at CMAM via direct neutron detection using miniBELEN and via activation with LaBr3(Ce) scintillators.

Acknowledgements:
This work has been supported by the Spanish Ministerio de Economía y Competitividad under grants FPA2017-83946-C2-1 & C2-2 and PID2019-104714GB-C21 & C22.

References
[1] S S Westerdale et al. Tech. report INDC(NDS)-0836 (2022)
[2] A Redondo-Cubero et al. Eur Phys J Plus 136 (2021) 175
[3] J Gómez-Camacho et al. Eur Phys J Plus 136 (2021) 273
[4] N Mont-Geli et al. arXiv:2205.02147 (2020)
[5] A R Garcia et al. Journal of Instrumentation 7 (2012) C05012
[6] V Vedia et al. Nucl Instrum Methods Phys Res A 857 (2017) 98

Speaker: N Mont-Geli (Institut de Tècniques Energètiques (INTE), Universitat Politècnica de Catalunya (UPC), Barcelona, Spain)

55 Nuclear research activities and open access program at GELINA facility

GELINA is an European Commission nuclear research facility installed at the JRC-Geel site in Belgium [1]. During more than 50 years, this neutron time-of-flight facility has been devoted to the measurement of neutron-induced cross sections. The main interest focus on nuclear energy applications but other research topics such as nuclear astrophysics or medical applications are considered. Their experimental capabilities are continuously upgraded, for instance, with an experimental setup for measuring fast neutron elastic and inelastic scattering cross sections, a new flight-path transmission station for measuring samples at high temperature or a new beamline in the target hall to study gamma-induced reactions.

GELINA takes part in the open access program to JRC Research Infrastructures [2]. This access is offered to researchers from EU Member States, candidate and associated countries. At this conference, we will present an overview of the results obtained within this open access framework.

[1] W. Mondelaers and P. Schillebeeckx, Notiziario Neutroni e Luce di Sincrotrone, 11 no2, 19-25 (2006).

[2] https://joint-research-centre.ec.europa.eu/knowledge-research/open-access-jrc-research-infrastructures_en

Speaker: Carlos Paradela

EUNPC_paradela_censored_1.pdf

56 Integration of the scattering chamber of the NUMEN experiment

The NUMEN experiment aims to measure double charge exchange reaction (DCE) cross sections with heavy-ion beams of unprecedented intensity interacting with specific isotopes [1]. DCE proved to be useful for getting information on the nuclear matrix elements of neutrinoless double beta decay, the most promising probe to establish the Majorana or Dirac nature of the neutrino, and to evaluate the effective neutrino mass.
The proposed technique was tested with pilot runs at INFN-LNS, in Catania, with the pre-existing magnetic spectrometer MAGNEX and ion beams.
However, to get statistical significance from such challengingly DCE low cross sections, higher intensity ion beams are required.
The super conducting cyclotron is being fully refurbished featuring ion beams with energy from 15 up to $70$ MeV/u and intensity up to $10^{13}$ pps at the reaction target point [2] and a complete upgrade of the MAGNEX spectrometer [3] including the scattering chamber (SC), where beam collides to target, is ongoing. The integration of this chamber with all the components around represents an important engineering challenge.
Inside the SC the target of the experiment consists of a thin isotope film evaporated on a graphite layer featuring high thermal conductivity. This layer is clamped in a target holder which holds it in position and it is connected to the cold finger of a cryo-cooler. To correctly align the target on the beam, the cryo-cooler will be vertically shifted by a regulation system; this system also allows the positioning of other spot of the target holder on the beam, useful for diagnostic purposes. Since the radiation level expected during experimental run will be non-negligible, an automatic system is designed for the manipulation of the target to manage the target replacement [4].
Downstream to the chamber a slits system will be positioned. It is composed by four different moving plates made in tantalum useful to control acceptance of MAGNEX spectrometer. This system also includes a pepper-pot to calibrate position measurement of the particles emerging from the target. For diagnostic purpose and for the measure of the incident beam charge during the runs a Fadaray Cup will be positioned inside the SC downstream of the target. All these systems are designed to work with remote settings and to cooperate each other with automatic procedures.
The integration of the beam lines with the SC is another challenging constraint to the design because it is required the connection to them with different incidence.
The external shape of the SC is imposed by the presence of gamma detectors to be positioned all around the main body. This necessity leads to the design of a spherical shape made in aluminium (series $5000$) to reach maximum efficiency to gamma detection.
Since the design of this integration is completed all the particulars are under manufacturing and the test of some subassemblies is already started to check compliance to the requirements and to define best procedures.
The system will be presented in details with actual first results of the testing.

References:

[1] - F. Cappuzzello et al., The NUMEN project: NUclear Matrix Elements for Neutrinoless double beta decay, European Physical Journal A 54 (5) 72 (2018). doi: doi.org/10.1140/epja/i2018-12509-3

[2] - C. Agodi et al., The NUMEN project: Toward New Experiments with High-Intensity Beams, Universe 2021 7 (2021) 72. doi: doi.org/10.3390/universe7030072

[3] – F. Cappuzzello et al., The NUMEN Technical Design Report, International Journal of Modern Physics A (2021) 36:30. doi: doi.org/10.1142/S0217751X21300180

[4] – D. Sartirana et al. For the NUMEN collaboration, Target Manipulation in Nuclear Physics Experiment with Ion Beams, Advances in Service and Industrial Robotics (Springer), (2020) 84:535-543. doi: doi.org/10.1007/978-3-030-48989-2_57

Speaker: Mr Diego Sartirana (INFN - Turin (IT))

EuNPC2022-NUMEN SC Integration - Sartirana.pdf

P2 Nuclear Structure, Spectroscopy, and Dynamics

57 Nuclear shapes from energy density functionals and heavy-ion collisions

The interpretation of the emergent collective behavior of atomic nuclei in terms of deformed intrinsic shapes is at the heart of our understanding of the rich phenomenology of their structure, ranging from nuclear energy to astrophysical applications across a vast spectrum of energy scales. A new window into the deformation of nuclei has been recently opened with the realization that nuclear collision experiments performed at high-energy colliders, such as the CERN Large Hadron Collider (LHC) or the BNL Relativistic Heavy Ion Collider (RHIC), enable experimenters to identify the relative orientation of the colliding ions in a way that magnifies the manifestations of their intrinsic deformation [1].

In this talk, I will present recent results obtained from the application of a state-of-the-art energy density functional framework to the description of some isotopes collided at high-energy at LHC and RHIC. In particular, I will show the first evidence of nonaxiality in the ground state of a nucleus, namely the $^{129}$Xe, observed in the context of ions collided at ultrarelativistic energies [2]. Indeed, comparing our results with LHC data obtained by the ATLAS Collaboration [3], we demonstrate that the later are only compatible with a triaxial deformation ($\beta \approx 0.2$, $\gamma \approx 30^\circ$) for the ground state of $^{129}$Xe, which is in good agreement with our nuclear structure calculations as well as recent experimental results from Coulomb excitation of the adjacent isotope $^{130}$Xe [4]. Finally, I will discuss new results on the heavy odd-mass nucleus $^{197}$Au.

[1] G. Giacalone, Phys. Rev. Lett. 124, 202301 (2020).
[2] B. Bally, M. Bender, G. Giacalone, and V. Somà, Phys. Rev. Lett. 128, 082301 (2022).
[3] ATLAS Collaboration, Conference Note ATLAS-CONF-2021-001 (2021).
[4] L. Morrison et al., Phys. Rev. C 102, 054304 (2020).

Speaker: Benjamin Bally

talk_bally_eunpc_26102022.pdf

58 Nuclear structure of exotic nuclei in the 132Sn region

The r-process produces roughly half of all nuclei heavier than iron, thus understanding the mechanism in which these nuclei are produced is an important topic of research. Properties of nuclei with magic numbers of neutrons are key to understanding the r-process. N=82 nuclei below $^{132}$Sn are connected to the mass abundance peak at A~130. In addition, studies of nuclei in this difficult to reach region provide information on nucleon-nucleon interactions and possible shell evolution.

Here we present experimental results obtained during the RIBF-189 experiment at RIKEN utilising the HiCARI high resolution germanium array. Particle identification was achieved on an event-by-event basis by the BigRIPS and Zero Degree spectrometers. New gamma-ray transitions have been observed for a large number of nuclei. Transitions from previously unseen configurations of $^{130}$Cd πg$_{9/2}$p$_{1/2}$ to the known yrast 4+ state π$g^2_{9/2}$ have been observed. This allows for the investigation of the proton-proton interaction below Z=50. Two tentative lines associated with single particle states decaying to the πg$_{9/2}$ ground state and πp$_{1/2}$ isomer have also been observed in $^{129}$Ag. This can be used to establish the proton single particle energies. Transitions observed in $^{132}$In and $^{130}$In provide information about the proton-neutron interaction above and below N=82 respectively. The obtained level schemes are supported by modern shell model and particle removal reaction calculations. Experimental details and physics results on these extremely neutron-rich nuclei will be presented.

Speaker: Mr T. Parry (University of Surrey)

eunpc2022.pdf

59 Quadrupole excitations in self-conjugate nuclei: pushing the limit.

In nuclei along the N = Z line, as protons and neutrons occupy the same valence orbitals, proton-neutron correlation properties and quadrupole-quadrupole interactions emerges. In heavy even N = Z nuclei the competition between prolate and oblate quadrupole coherence is hitherto not measured. Well-developed deformation in the upper $fpg$ shell starts from $^{68}$Se. In $^{68}$Se, the intrinsic deformation of the ground-state band has been interpreted as oblate, while a prolate deformation is assigned to the excited band that soon becomes yrast. The tendency leads to the emergence of shape coexistence, which are predicted in the strongly deformed $^{72}$Kr, $^{80}$Zr and $^{84}$Mo [1].
In this study, exploiting an $^{86}$Mo radioactive beam produced at NSCL, we measured the lifetime of the first 2$^+$ state in $^{84}$Mo and $^{86}$Mo using the GRETINA array and a plunger setup. The reduced transition probability B(E2; 2$^+$ → 0$^+$) of the Mo isotopes were deduced, thereby understanding their quadrupole collectivity and deformation.
The experimental results will be presented along with their interpretation with state-of-the-art calculations using ZBM3 effective interaction
[1] A. P. Zuker, A. Poves, F. Nowacki, and S. M. Lenzi, Phys. Rev. C 92, 024320 (2015).

Speaker: Francesco Recchia (Universita e INFN, Padova (IT))

Recchia_Quadrupole_excitations_in_self_conjugate_nuclei_pushing_the_limit_02 - web.pdf

60 Transfer Reactions with ACTAR TPC: highlights from the first campaign @ GANIL

Direct reactions are fundamental tools to investigate the structure of exotic nuclei. Studies of nuclei far away from stability are usually performed with secondary radioactive beams, that suffer from low intensities and need to be compensated with thick targets and high efficient detection systems to increase luminosity. Active targets are invaluable devices that, among other important features, allow to reconstruct the reaction in three dimensions without loss of resolution.

The ACtive TArget and Time Projection Chamber (ACTAR TPC) detector has been developed at GANIL to cover a broad physics programme. The device was commissioned in 2018 showing an excellent performance of the detector. Since then, several experiments have been performed at GANIL. In this talk, I will present the physics motivation and some preliminary results with special focus on the foreseen achievements for transfer reactions with active targets.

Speaker: Beatriz Fernandez Dominguez (Universidade de Santiago de Compostela (ES))

BFernandezDominguez_EuNPC22_vf.pdf

61 Variations on Nuclear Shapes

The concept of nuclear shape, most often of quadrupole type, is ubiquitous
in nuclear physics. We speak of spherical, prolate, oblate or triaxial nuclei;
of the evolution of the shapes along isotopic or isotonic chains, and of the
coexistence of different shapes in the spectrum of a given nucleus. The
last two phenomena, are closely related and prominent at the very neutron
rich edge of the nuclear chart, in particular at the Islands of Inversion which
occur around the neutron magic numbers N=20, 28, 40 and 50. In these cases,
the latter acts as the portal to the IoI’s where the shape evolution takes place. However,
the very notion of shape is intimately linked to our semiclassical view of the nucleus
or, in other words, it only makes sense when a description in the intrinsic reference
frame is valid. Thus, how can we characterize the nuclear shape in the laboratory?
The only invariant quantities at hand are the scalars made from the quadrupole
operator $\hat{Q}_2$ usually known as Kumar invariants. Only recently the higher order
invariants (up to $(\hat{Q}_2)^6$) needed to obtain not only the values of $\beta$ and $\gamma$ but also
its variances, have been calculated. I will present a panoply of results which
question some of our long time cherished semantics, because in many cases nuclei
exhibit a non negligible degree of $\beta$ softness, and in most cases they are fully
$\gamma$ soft. We submit that when the variances of $\beta$ and $\gamma$ are
large the notion of shape makes no sense. In particular, there is not such a thing
as a spherical nucleus.

Speaker: Prof. Alfredo Poves (Departamento de Física Teórica, Universidad Autónoma de Madrid)

EuNPC2022.pdf

P2 Nuclear Structure, Spectroscopy, and Dynamics

62 Nuclear structure studies at the ISOLDE Decay station

The ISOLDE Decay Station (IDS) [https://isolde-ids.web.cern.ch/] was designed as a flexible tool for decay spectroscopy studies, operating since 2014 at ISOLDE. At the core of IDS there are 4-6 HPGe clovers to detect $\gamma$ rays with high energy resolution together with a moving tape system and a complex array of ancillary detectors such as LaBr$_3$:Ce crystals to measure excited-state lifetimes down to a few picoseconds, silicon detectors (annular, PAD, DSSSD, Solar Cell) for charged particle (p, $\alpha$, e$^-$, e$^+$) or $\beta$-delayed fission fragments spectroscopy and an efficient plastic scintillator array acting as a neutron Time-of-Flight detector for $\beta$-delayed neutron emission studies. In recent years, IDS has also been used as a decay-spectroscopy tool for in-source laser spectroscopy studies together with RILIS.

Following the end of the CERN Long Shutdown (2019-2020) development campaign, ISOLDE has resumed experiments in June 2021 and there have been several new decay spectroscopy experiments performed at IDS: laser spectroscopy of neutron-rich Tl, Po and At isotopes; fast timing studies around neutron-rich Cu and Cd, beta-delayed neutron spectroscopy of $^8$He. These measurements will be highlighted in the current presentation alongside a detailed description of the setup and future development plans for IDS.

Speaker: Razvan Lica (Horia Hulubei National Institute of Physics and Nuclear Engineering (RO))

RazvanLica_IDS_2022_EuNPC.pdf

63 Proton-neutron pairing, α-like quartetting and ground/excited states of nuclei close to N=Z line

Various studies have shown that the proton-neutron (pn) pairing correlations can be accurately described not by a condensate of Cooper pairs, as considered in the majority of mean-field calculations [1, 2], but by a condensate of α-like quartets [3, 4, 5, 6, 7]. After a short review of the quartet condensate model (QCM), I shall discuss the effect of the pn pairing on the ground states of nuclei with N-Z=0.2,4, analyzed recently in the framework of Skyrme-HF+QCM calculations [9]. An interesting aspect pointed out by these calculations is the strong interdependence between all types of pairing correlations. In particular, when the isoscalar pn pairing channel is switched on, the pairing correlations are redistributed among all the pairing channels without changing significantly the total pairing energy. Due to this reason, for the majority of N ≈ Z nuclei, the binding energy is not affected much when the isoscalar pairing channel is switched on. Yet, in all calculations which include both the isovector and the isoscalar pairing forces, the isoscalar pairing correlations contribute significantly to the binding energies and coexist always with the isovector pn pairing. Finally I will present a recent extension of the QCM approach to the excited stated of pn pairing Hamiltonians [8]. It will be shown that the low-lying excited states of N = Z systems can be described by breaking a quartet from the ground state condensate and replacing it with an “excited” quartet, an approach which is analogous to the one-broken-pair approximation employed for like-particle pairing.

References

[1] A. L. Goodman, Phys. Rev. C 63, 044325 (2001).
[2] A. Gezerlis, G. F. Bertsch, and Y. L. Luo, Phys. Rev. Lett. 106, 252502 (2011).
[3] N. Sandulescu, D. Negrea, J. Dukelsky, C. W. Johnson, Phys. Rev. C 85, 061303(R), (2012). [4] N. Sandulescu, D. Negrea, and D. Gambacurta, Phys. Lett. B 751, 348 (2015).
[5] M. Sambataro and N. Sandulescu, Phys. Rev. C 93, 054320 (2016).
[6] D. Negrea, P. Buganu, D. Gambacurta, N. Sandulescu, Phys. Rev. C 98, 064319 (2018).
[7] M. Sambataro and N. Sandulescu, J. Phys. G: Nucl. Part. Phys. 47, 11, (2020).
[8] M. Sambataro and N. Sandulescu, Phys. Lett. B 820, 136476 (2021).
[9] D. Negrea, N. Sandulescu and D. Gambacurta, Phys. Rev. C 105, 034325 (2022).

Speaker: Prof. Nicolae Sandulescu (National Institute of Physics and Nuclear Engineering, Magurele-Bucharest, Romania)

64 Nuclear Structure of Light Neutron-Rich Transition Metals via Mass Measurements at TITAN

High precision mass measurement of exotic nuclei play an important role in shaping our understanding of the nucleus. It has become evident that the structure of the nucleus can change away from the valley of beta stability; new phenomena, as e.g. shell quenching, weakening or disappearance of classical and appearance of new magic numbers have been observed via characteristic signatures in the mass surface.

TRIUMF’s Ion Trap for Atomic and Nuclear science (TITAN) [1] located at the Isotope Separator and Accelerator (ISAC) facility, TRIUMF, Vancouver, Canada is a multiple ion trap system specialized in performing high-precision mass measurements and in-trap decay spectroscopy of short-lived radioactive species. Although ISAC can deliver high yields for some of the most exotic species, many measurements suffer from strong isobaric background. This limitation has been overcome by the installation of an isobar separator based on the Multiple-Reflection Time-Of-Flight Mass Spectrometry (MR-TOF-MS) technique [2]. In this device mass selection is achieved using dynamic re-trapping of the ions of interest after a time-of-flight analysis [3]. Re-using the injection trap of the device for the selective re-trapping, the TITAN MR-TOF-MS can operate as its own high resolution isobar separator prior to a mass measurements within the same device. This unique combination of operation modes boosts the dynamic range and background handling capabilities of the device, enabling high precision mass measurements of ions of interests with minuscule yields from strong background.

This contribution will discuss recent results of mass measurements of neutron-rich transition metals addressing the evolution of the exotic N=32 neutron shell closure and the N=40 island of inversion. Mass measurements of the most exotic light transition-metals, elements between Sc and Fe, were made possible due to new laser ion source development combined with the highly sensitive TITAN MR-TOF-MS. The new results shine light on the nuclear structure in this region of then nuclear chart.

References:
[1] J. Dilling et al., NIM B 204, 2003, 492–496
[2] C. Jesch et al., , Hyperfine Interact. 235 (1-3), 2015, 97–106
[3] T. Dickel et al. J. Am. Soc. Mass Spectrom. (2017) 28: 1079

Speaker: Moritz Pascal Reiter (University of Edinburgh)

EUNPC 2022 - structure of transition metals_version2.pptx

65 Study of elastic and inelastic scattering and one-nucleon transfer reactions for the system $^{18}$O$+^{48}$Ti within the NUMEN project

The $^{18}$O$+^{48}$Ti reaction was studied at 275 MeV incident energy for the first time under the NUMEN [1] experimental campaign with the main goal of investigating the $^{18}$O$(^{48}$Ti,$^{48}$Ca$)^{18}$Ne double charge exchange (DCE) process. The measurements were performed at the INFN-LNS in Catania, using the MAGNEX large acceptance magnetic spectrometer [2]. To fully understand the direct meson-exchange DCE mechanism, the contribution of other competing processes leading to the same final states should be quantified. In the context of this multi-channel approach, the study of the elastic and inelastic scattering is fundamental, because the former gives access to the optical potential, while the latter allows to investigate the nuclear deformations. Moreover, the analysis of such channels permits to deduce the initial state interaction, which is an essential ingredient for the description of all the nuclear transitions involved in the reaction network. To this extent, the elastic and inelastic experimental cross section angular distributions were deduced and theoretically analyzed within the distorted-wave Born approximation and the coupled channel formalisms in order to explore the role of the couplings to the low-lying excited states of both projectile and target. Recent results on the analysis of the one-proton [3] and one-neutron transfer reactions will be also presented.

References
[1] F. Cappuzzello et al., Eur. Phys. J. A 54 (2018) 72.
[2] F. Cappuzzello et al., Eur. Phys. J. A 52 (2016) 167.
[3] O. Sgouros et al., Phys. Rev. C 104 (2021) 034617.

Speaker: Giuseppe Antonio Brischetto (UniCt, INFN-LNS)

Brischetto-EuNPC2022.pdf

P3 Nuclear Astrophysics

66 Study of ion-ion fusion mechanisms at sub-barrier energies for nuclear astrophysics

For the last 5 years, the Nuclear Astrophysics Group (NAG) at IFIN-HH has been carrying out a campaign to study fusion reactions important in stellar nucleosynthesis, at sub-Coulomb barrier energies. More recently, we have been focusing on reactions between 12C and 16O nuclei, as they define stellar scenarios in various important evolution phases of massive stars.

In the past, this has been done by irradiating targets of interest at the 3 MV Tandetron facility and measuring their deactivation in the ultra-low background laboratory sitting inside the Slanic salt mine. This allowed us to reach cross-sections of the order of hundred pb for the reaction 13C+12C. As a neighboring reaction to the very important 12C+12C, these measurements provided significant insight into the behavior of the cross-section at very low energies and the fusion mechanisms that are theorized to take place.[1]

In this presentation, I will show preliminary results from the measurement of 13C+16O, the next reaction of interest for our study. It was chosen because it is a neighboring system to 12C+16O with an extra neutron that produces decaying channels which can be measured through deactivation. Related to that, I will also touch upon the BeGa detection station that was recently developed to measure unstable nuclei which are too short-lived to be taken to the Slanic mine.

[1] N. Zhang, D. Tudor et al, Phys. Lett. B 801, 135170 (2020).

Speaker: Dr Alexandra Spiridon (National Institute of Physics and Nuclear Engineering IFIN-HH)

67 Measurement of 27(alpha, n gamma)30 P reaction yields.

Reactions induced by alpha particles on stable elements play a relevant role in several scientific fields, from nuclear technologies and nuclear
astrophysics, to dark matter searches and neutrino physics. Accurate data on the neutron yield from the interaction of $\alpha$-particles with nuclei via $(\alpha,n)$ reactions are of particular interest in this context, both due to the inconsistency of the available experimental data in the literature and to the renewed interest for novel applications. The need for new measurements with
higher precision has been recently recognized [1].

In this work we focus on reactions induced by alpha particles on stable Al, a common reaction that has been propose as a benchmark to intercompare measurements and cross check experimental techniques. In particular we focus on the measurement of $^{27}{Al}(\alpha,n)$ reaction yields via activation and $^{27}{Al}(\alpha, n \gamma)$ production yields. The measurements have been performed in the framework of a wider effort by the Spanish MANY collaboration, whose ultimate goal is the measurement of $(\alpha,xn)$ production yields, reaction cross-sections and neutron energy spectra.

The main objective of this work was the commissioning of the detector system and the new experimental beamline via the previously measured $^{27}{Al}(\alpha,n)^{30}{P}$ reaction. The experiment was carried out at the CMAM laboratory in Madrid [2], Spain using an array of LaBr$_3$(Ce) FATIMA-type [3] detectors placed at selected
angles in the laboratory frame. The gamma spectroscopy measurements allow to determine the total reaction yield from the decay of the activation products and the $(\alpha,n \gamma)$ yield from the de-excitation of the states in the target nuclei. The setup was complemented by a neutron monitoring unit based on a $^{3}{He}$-filled neutron proportional counter embedded high-density
polyethylene, and a high-resolution HPGe detector to aid gamma-ray
identification.

The presentation will address the thick-target yields obtained by activation in the 5 to 9 MeV energy range, the gamma yield resulting for the $^{27}{Al}(\alpha,n)$ reaction as a function of energy, and the effect of angular correlations on the experimentally obtained gamma yields.

References.

[1] S. Westerdale et al., Tech. Report INDC (2022) NDS-0836

[2] A. Redondo-Cubero et al., Eur. Phys. J. Plus 136 (2021) 175

[3] V. Vedia et al., Nucl. Instrum. Methods A 857 (2017) 98

Speaker: Odette Alonso-Sanudo Alvarez (Universidad Complutense (ES))

68 The pp neutrino flux and 205Pb/205Tl s-process chronometry

Recent measurements performed at the GSI facilities have experimentally determined the value for the rate of 205Tl bound-state beta decay. This in turn allows to ascertain the nuclear transition matrix element to the first excited state of 205Pb. This information plays a crucial role in a twofold way.
On one hand, the bound-state beta decay of 205Tl could counter balance the 205Pb electron capture and keep the 205Pb production high during s-process nucleosynthesis, affecting the 205Pb/204Pb ratio and clarify the plausibility for the source of the live 205Pb in the early Solar System.
On the other hand, the capture of solar pp-neutrinos (0≤Eν≤420 keV) allows the transmutation of 205Tl nuclei into 205Pb. The energy threshold for this reaction is Eν≥52 keV, by far the smallest threshold for any known neutrino-induced nuclear reaction. The nuclear transition matrix element to the first excited state of 205Pb can be determined from the one of the bound-state beta decay of 205Tl to this state as the dominant contribution to the nuclear transition matrix is the same.
This work is funded by SFB 1245, Institute für Kernphysics, TU Darmstadt.

Speaker: Dr Riccardo Mancino (TU Darmstadt, GSI)

EuNPC22_Mancino.pdf

P5 Heavy Ion Collisions and QCD Phases

69 Status of soft probes and the initial condition of the quark-gluon plasma

A central question in the phenomenology of relativistic heavy-ion collisions is how the initial state of the quark-gluon plasma (QGP) is precisely shaped. This contribution reports on recent groundbreaking advances concerning our understanding of the initial state of the QGP resulting from global Bayesian analyses (and their shortcomings) of soft probes. Ideas for future directions of investigation are pointed out.

Speaker: Giuliano Giacalone (Universität Heidelberg)

Giacalone_talk#1.pdf

70 Hard probes in heavy-ion collision (theory)

In this invited talk I will first present an overview on the theory of hard probes, one of the major tools to study the properties of the quark-gluon plasma in heavy-ion collisions. Then, I will focus on some recent theoretical developments in our understanding of one main type of hard probes: QCD jets.

Speaker: Bin Wu

HP_Wu.pdf

71 New jet results with ALICE

Jets are useful probes of the QGP produced in heavy-ion (HI) collisions because the hard scattered partons lose energy with the medium when they traverse through it, a phenomena called jet quenching, which results in the suppression of jet yields and modification of internal jet structure. Measurements of jet quenching will be shown using new observables and techniques in order to access new regions of phase space in ALICE. Additionally, results of photon-tagged and heavy flavor-tagged jets will be discussed which provide insight about the flavor and mass dependence of jet quenching. This talk will discuss these new results, including comparisons to different quenching models, and how they further our knowledge of the QGP. This talk will also discuss new results in small systems with ALICE, including measurements of isolated hard photons, and how they fit into our understanding of QCD matter.

Speaker: Hadi Hassan (University of Jyvaskyla (FI))

EUNPC22_Hadi_Hassan.pdf

72 Quarkonium production and elliptic flow in small systems with ALICE

Quarkonium production has long been identified as one of the golden signatures of the quark-gluon plasma (QGP) formation in heavy-ion collisions.
The LHC data from small colliding systems, namely pp and p--Pb, showed unexpected QGP-like behaviours when selecting high multiplicity events. These results include the non-zero elliptic flow of identified hadrons and the strangeness enhancement observed in high-multiplicity pp and p--Pb collisions. Multiple parton-parton interactions (MPI) taking place in a single hadron-hadron collision are one of the main explanations for these observations.
Quarkonium studies in small systems offer several ways to probe MPI, in particular through measurements of double quarkonium production as well as quarkonium production as a function of the charged-particle multiplicity. In addition, measurements of elliptic flow ($v_2$) of quarkonia in small systems enable to investigate collective effects in the heavy flavour sector. Moreover, heavy quarkonium production in hadronic collisions is sensitive to both perturbative and non-perturbative aspects of quantum chromodynamics (QCD). Therefore, quarkonium production and polarization measurements in pp collisions also represent a benchmark test of QCD based models.

In this contribution, the multiplicity dependent production of quarkonium states, such as J/$\psi$, $\psi$(2S) and $\Upsilon$(nS), reconstructed with the ALICE detector in pp and p-Pb collisions, will be presented together with their excited-to-ground state ratios. New J/$\psi$ results in pp collisions at $\sqrt{s}$ = 13 TeV and forward rapidity will be shown, in particular the $v_2$ in high multiplicity pp collisions, the measurement of the J/$\psi$ pair production and $\Upsilon$(1S) polarization. Recent quarkonium cross section measurements in pp collisions at mid and forward rapidity will also be presented. Results will be compared with available model calculations.

Speaker: Giacomo Alocco (Universita e INFN, Cagliari (IT))

EuNPC22_Giacomo_Alocco.pdf

P8 Nuclear Physics Applications

73 Studies of radio-isotope production relevant for medical imaging using laser-driven ion beams

Medical imaging based on the radiation emitted by unstable nuclei is used on a daily basis as a fundamental tool in medical diagnosis, particularly thanks to techniques such as PET (Positron Emission Tomography) or SPECT (Single-Photon Emission Computed Tomography). This has led to an increase in the demand of nuclear radio-isotopes, with the production typically being done at conventional accelerators (cyclotrons) and dedicated nuclear reactors. However, due to the large footprint and associated cost of these production facilities, their feasibility and economic viability relies on the mass-scale production of supplies that cover large areas, typically regional or national scale. As a result, a single production facility must provide nuclides to health centres in distances that range up to 100s of km. In the particular case of the $\beta^+$ emitters used in PET imaging, this approach has limited the range of isotopes to $^{18}$F. With a half-life of $\sim110\,$min, $^{18}$F can endure the time required for the production, post-processing and distribution. Other radio-isotopes of interest in medical imaging, such as $^{11}$C, $^{13}$N, or $^{15}$O, have lifetimes too short to be commercially available.

In this context, there has been a growing interest in compact accelerators that can be used for the production of isotopes. A particularly promising alternative is the use of ultra-intense lasers as drivers of energetic ion beams, with advantages such as flexibility, compactness and cost-effectiveness. Although there are several mechanisms for laser-based ion acceleration, Target Normal Sheath Acceleration (TNSA) is arguably the most interesting mechanism. In TNSA, an ultra-intense laser pulse ($I>10^{18}$W\,cm$^{-2}$) interacts with a thin (few micron), metallic target, leading to the acceleration of light ions to energies in the MeV range with appealing properties, such as ultra-short duration, small source size, and low emittance. Thanks to the closely-coupled setup, with the laser-plasma interaction being limited to a region of a few micron, the shielding requirements are significantly lowered with respect to conventional accelerators. Such a laser-based accelerator would therefore constitute an affordable option for hospitals, clinics, and research centres, enabling the on-demand production of radio-isotopes, including those with shorter lifetimes.

Here, we present some recent results and technological developments achieved using the STELA system, a 30\,TW laser deployed at the Laser Laboratory for Acceleration and Applications (L2A2), in the University of Santiago de Compostela (Spain). These developments in targetry, diagnostics, and secondary production of radio-nuclides open the path for this technology to become a real alternative to the commercial generation of medical radio-isotopes.

Speaker: Aaron Alejo Alonso (Universidade de Santiago de Compostela)

74 Radiobiology experiments with laser-induced radiation sources: exploring the UHDR regime

Since the development of the Chirped Pulse Amplification (CPA) technique, both the generation of ultra-short and ultra-intense laser pulses, and its applications in nuclear physics have become a very active field of research. When a laser pulse of these characteristics impinges on a solid target, different particle acceleration mechanisms can take place depending on several parameters such as the laser intensity on focus, its angle of incidence or the target thickness [1]. This results in the capability of generating pulsed radiation sources such as x-rays or polyenergetic proton beams for preclinical research. In addition, the particle acceleration occurs due to the generation of electric fields of the order of TV/m within a few microns, so laser-driven acceleration gives rise to compact alternatives to conventional radiofrequency accelerators. These laser-induced radiation sources can produce relevant doses in short periods of time, which makes them suitable for radiobiological research related to Ultra High Dose Rate therapy techniques (UHDR/FLASH) [2].

The Laser Laboratory for Acceleration and Applications (L2A2) of the University of Santiago de Compostela (USC) is equipped with two laser beamlines. With the low energy line (1 mJ per pulse, 35 fs, 1 kHz repetition rate) impinging on a copper target, we have developed a stabilized, table-top x-ray source for in vitro irradiation in radiobiology experiments. The dose deposition has been measured with radiochromic films, and we report a peak dose rate of $10^9$ Gy/s. To test its suitability for systematic experiments, we have irradiated an in vitro model of alveolar epithelium using the A549 human lung adenocarcinoma cell line at several exposure times and dose values. DNA double-strand breaks (γ-H2AX foci) and DNA damage response events (53BP1 foci) were quantified, showing a linear response with the delivered dose in this first proof-of-concept.

At the same time, we have set up a proton source using the high energy laser output, which delivers 1.2 J, 25 fs pulses at a 10 Hz repetition rate. We have designed and built an experimental setup for in vitro irradiation of cell cultures, which comprises a magnetic energy selector that allows for the separation of the broad energy proton spectrum into monoenergetic beamlets with energies up to a few MeV [3]. In addition, several passive (CR-39, RCF) and active detectors (TOF, online dose monitor) have been developed and installed to fully characterize the proton spectrum in terms of fluence and dose delivery. We expect a proton fluence of $10^6$ $cm^{−2}$ over the surface of the cell culture dish, and a dose deposition ranging from 18 to 65 mGy per shot, depending on the chosen proton energy beamlet.

[1] A. Macchi, A superintense laser-plasma interaction theory primer, Springer (2012).
[2] P. Chaudhary et al, Frontiers in Physics 9 (2022).
[3] A. Torralba et al, Quantum Beam Science 6(1), 10 (2022)

Acknowledgements: Project RTI-2018-101578-B-C22 financed by MCIN/AEI/10.13039/501100011033 and FEDER "Una manera de hacer Europa". Project AICO/2020/207 financed by Generalitat Valenciana. Research co-financed by the European Union through Programa Operativo del Fondo Europeo de Desarrollo Regional (FEDER) of the Comunitat Valenciana, IDIFEDER/2021/004.

Speaker: Alicia Reija (Instituto Galego de Física de Altas Enerxías (IGFAE), Universidade de Santiago de Compostela, Spain; Instituto de Instrumentación para Imagen Molecular (I3M), CSIC – Universitat Politècnica de València, Spain)

75 First steps towards on-the-fly dose reconstruction from in-beam PET activation

In-beam Positron Emission Tomography is a promising technique aimed to solve the problem of range verification in proton therapy. In this work we report the first results using a novel in-beam portable PET system that can detect and process on-the-fly the β+ activity produced during and after irradiation.
The specific PET setup consisted of 6 phoswich detector blocks with 338 pixels each, with of 1.55x1.55 x LYSO (7mm)+GSO (8mm) . The system was coupled to a fast data acquisition system able to sustain rates up to 10 Msingles/sec. Two different PMMA targets were irradiated with monoenergetic clinical proton beams at the Quirónsalud proton therapy center. The 3D maps of the activity were reconstructed on-the-fly every 0.5 seconds and with a 0.5 mm spatial resolution. We also assessed the system response to changes in the position and direction of the beam during irradiation.
This validates the experimental setup to be used for in-beam on-the-fly reconstruction of the 3D activity and provides a gold standard to obtain the deposited dose distribution when combined with a fast dose reconstruction method.

Speaker: Ms ANDREA ESPINOSA RODRÍGUEZ (Grupo de Física Nuclear, EMFTEL & IPARCOS, Universidad Complutense de Madrid, CEI Moncloa, Madrid, Spain)

76 Experimental tests of the scanner prototype for imaging with protons developed at IEM-CSIC

Proton therapy requires precise knowledge of the patient's anatomy to guarantee an accurate dose delivery [1]. X-ray computed tomography (CT) images are used nowadays to calculate the relative stopping power (RSP) needed for proton therapy treatment planning [2]. Recent studies indicate that tomographic imaging using protons has the potential to provide a more accurate and direct measurement of RSP with a significantly lower radiation dose than X-rays [3].
The proton CT (pCT) scanner prototype developed at IEM-CSIC is composed of a tracking system of two double-sided silicon strip detectors, and the CEPA4 detector as the residual energy detector. Our pCT scanner prototype was tested at the Cyclotron Centre Bronowice (CCB) facility in Krakow, Poland during the first week of June 2021. The planar imaging capabilities of our pCT scanner prototype were studied using three different planar phantoms of aluminum and PMMA. Radiography images were reconstructed from pixelated detectors, and they were converted into continuous images by uniformly distributing the statistics of each pixel over the pixel area. The radiography images displayed great fidelity with respect to the shapes of the phantoms. The spatial resolution of this proton imaging scanner prototype is better than 2 mm and the MTF-10%=0.3 line pairs per mm [4]. Likewise, volumetric phantoms composed of cylindrical matrices made of PMMA with air, alcohol, and water structures were imaged at different angular positions. The reconstructions of the three-dimensional phantoms are being studied to determine the spatial resolution and the RSP resolution of our prototype. The resulting values of the RSP are compared with the experimental values reported in Ref. [5], and they display a good agreement. The continuation of this work includes a new experiment carried out in June 2022 at the CCB facility. This new experiment aimed to study more complex phantoms with proton beams with energies around 200 MeV.
At this conference, I will present the imaging capabilities of our pCT scanner prototype, alongside the status of the data analysis of the second test performed last June.

References
[1] C. Sarosiek et al., Med. Phys. 48, 2271 (2021).
[2] P. Wohlfahrt and C. Richter, Br. J. Radiol. 93, 20190590 (2020).
[3] R. P. Johnson Rep. Prog. Phys. 81, 016701 (2018).
[4] J. A. Briz et al., IEEE Trans. Nucl. Sci. 69, 696 (2022).
[5] J. K. van Abbema, et al., Nucl. Instrum. Methods Phys. Res. B 436, 99 (2018).

Speaker: AMANDA NATHALI NERIO AGUIRRE (Instituto de Estructura de la Materia - CSIC)

ANNerio_EuNPC22.pptx

17:15 Coffee Break

P1 Accelerators and Instrumentation

77 RECENT RESULTS ON THE FRAISE FACILITY AT INFN-LNS

N.S. Martorana 1,2, L. Acosta 3,4, C. Altana 2, A. Amato 2, L. Calabretta 2, G. Cardella 5, A. Caruso 2, L. Cosentino 2, M. Costa 2, E. De Filippo 5, G. De Luca 2, E. Geraci 1,5, B. Gnoffo 1,5, C. Guazzoni 4, C. Maiolino 2, E.V. Pagano 2, S. Pirrone 5, G. Politi 1,5, S. Pulvirenti 2, F. Risitano 5,6, F. Rizzo 1,2, A.D. Russo 2, P. Russotto 2, D. Santonocito 2, A. Trifiró 5,6, M. Trimarchi 5,6, S. Tudisco 2, G. Vecchio 2

1 Dipartimento di Fisica e Astronomia Ettore Majorana, Università degli Studi di Catania, Italy, 2 INFN-LNS, Catania, Italy, 3 Instituto de Fìsica, Universidad Nacional Autònoma de México, Mexico City, México, 4 DEIB Politecnico Milano and INFN Sez. Milano, 5 INFN-Sezione di Catania, Italy, 6 Dipartimento MIFT, Universitá di Messina, Italy

A dedicated facility consisting in a new fragment separator named FRAISE (FRAgment In-flight SEparator) is under construction at INFN-LNS. This facility will be able to exploit light and medium mass primary beams with a power up to ≈ 2-3 kW to produce RIBs (Radioactive Ion Beams) by means of the in-flight technique [1-4]. The high intensity achievable with FRAISE requires the use of suitable diagnostics and tagging devices, capable of also operating in a hard radioactive environment. In the present contribution we discuss the latest results of the FRAISE apparatus, with a particular focus on the diagnostics and tagging devices as well as the RIBs available thanks to the use of FRAISE.

[1] Russotto P. et al., Jour. of Phys. Conf. Ser., 1014 (2018) 012016 and references therein.
[2] Russo A.D. et al., NIM B, 463 (2020) 418.
[3] Martorana N.S., Il Nuovo Cimento 44 C (2021) 1.
[4] Martorana N.S., Il Nuovo Cimento 45 C (2022) 63.

Speaker: Nunzia Simona Martorana (Dipartimento di Fisica e Astronomia "Ettore Majorana" and INFN-LNS, Catania, Italy)

78 New detectors for capture (n, γ) cross section measurements at n_TOF: the Segmented Total Energy Detector (sTED) and the HIDALGO project

The neutron time-of-flight facility n_TOF [1] is a pulsed neutron source for time-of-flight measurements mainly devoted to perform neutron cross section measurements. It is characterised by high instantaneous neutron intensity, high-resolution and broad neutron energy beams. Two time-of-flight experimental areas are available at the facility: Experimental ARea 1 (EAR1), located at the end of the 185 m horizontal flight path from the spallation target, and Experimental ARea 2 (EAR2) [2], placed at 20 m from the target in the vertical direction. The EAR2 was built in 2014 to carry out challenging cross-section measurements with low mass samples (<1 mg), reactions with small cross-sections or highly radioactive samples.

At n_TOF EAR1 more than 50 capture cross section measurements have been performed with big C6D6 liquid detectors (~1 L)[3]. These detectors used at EAR1 were not optimised to perform capture measurements in EAR2, mainly due to the ~300 times instantaneous neutron flux of EAR2 compared to EAR1. For this reason, the¬ Segmented Total Energy Detector (sTED) was developed. This detector consists of a physically segmented array of small C6D6 liquid detectors (0.05 L) with reduced size photosensors. The segmentation reduces the high counting rates and the saturation of high energy signals originated in the spallation process. The sTED has been validated to perform capture measurements, at least until 300 keV neutron energy at EAR2. At the moment, 9 sTED modules have been used to perform various capture measurements (94,95,96Mo, 79Se, 94Nb and 160Gd).

Apart from the sTED detector, the HIDALGO project will be presented, which is also focused in capture measurements. In this case, the project is a Spanish collaboration inside n_TOF with the objective to design and build innovative and highly-performing capture detectors for EAR1 and/or EAR2.

References

[1] Guerrero, C. et al. Eur. Phys. J. A 49, 27 (2013).
[2] C. Weiss, et al Nuc. Inst. Meth. Phy. Res. Sec. A, 799:90–98, (2015).
[3] R. Plag et al., Instrum. Meth. Phys. Res. A

Speaker: Alberto Pérez de Rada Fiol (CIEMAT)

22_10_EuNPC_sTED_v01.pdf

P2 Nuclear Structure, Spectroscopy, and Dynamics

79 Core-valence absorption in breakup and stripping reactions and itsisospin dependence

Nucleon removal reactions at intermediate energies have proven of great value to extractspectroscopic information from exotic atomic nuclei. For the case of nucleon removal at inter-mediate energies, a trend was noticed in the early 2000s in which cross sections were found tobe significantly overestimated for the removal of deeply-bound nucleons in asymmetric nuclei,while the removal of the weakly-bound species in these same nuclei did not present such anoverestimation [1]. The fact that this trend has not been observedin transfer or knockoutreactions with proton targets ($p, pN$) urges for the reevaluation of the description for thesereactions [2].
After nucleon removal, removed nucleon and residual nucleus (thecore) are left in a stateof medium or high relative energy, and their interaction can lead to the destruction of the core,which results in a reduction of the cross section. This effect would naturally be more intensein the removal of more deeply-bound nucleons, which interact morestrongly with the core, buthas not been considered in standard calculations of nucleon removal reactions until now.
In order to assess the importance of this effect, in this contribution we extend the usualdescription of breakup reactions (where both removed nucleon and core are detected) via Continuum-Discretized Coupled-Channels (CDCC) [3] to include the absorption between nu-cleon and core through an expansion in the eigenstates of a complexpotential which describesthis absorption, correcting for their non-orthogonality throughthe use of a biorhogonal basis[4], applying these results to neutron breakup of $^{11}$Be and $^{41}$ Ca on $^{12}$C targets at energies of 70MeV/A.
We also present some preliminary results for stripping reactions (where the removed nucleonis absorbed and only the core is detected), where absorption is modelled via an effective den-sity, focusing on the modification of the “quenching factors” and their dependence on isospinasymmetry, where we find a significant reduction in this dependence.
[1] A. Gadeet al, Phys. Rev. C77, 044306 (2008)
[2] T. Aumannet al, Prog. Part. Nucl. Phys.118, 103847 (2021)
[3] N. Austernet al, Phys. Rep.154, 125 (1987)
[4] B. H. McKellar and C. M. McKay, Aust. Jour. Phys.36, 607 (1983)

Speaker: Mario Gómez Ramos (TU Darmstadt)

Pres_Eunpc.pdf

80 Lifetime measurements of low-lying states in midshell Te isotopes

Transition probabilities for the yrast $2^+$ states in the midshell Te isotopes, 2 protons above Sn, are theoretically interesting in order to test shell model predictions. However, some values are still missing and some values have an error too large to successfully test shell model parameters. We have measured the lifetime of the $2^+$ to $0^+_{gs}$ transition in neutron deficient $^{118}$Te, using the DPUNS plunger and the JUROGAM II gamma-ray spectrometer at the JYFL accelerator laboratory, with the intention of decreasing the uncertainty in the adopted value. Furthermore, we aim to extend the analysis to include the currently unknown lifetime of the $2^+$ to $0^+_{gs}$ transition in $^{116}$Te.

Speaker: Ebba Ahlgren Cederlöf (Uppsala University & KTH Royal Institute of Technology)

Presentation___Lifetime_of_the_2__state_in_Tellurium.pdf

81 Energy dependence of fission yields investigated using quasi-free (p,2p) scattering reactions on 238U in inverse kinematics

In the last decade, unprecedented fission experiments have been carried out at the
GSI/FAIR facility using the inverse kinematics technique in combination with state-
of-the-art detectors. For the first time in the long-standing history of fission, it was
possible to simultaneously measure and identify both fission fragments in mass and
atomic numbers [1] and obtain many correlations among them sensitive to the fission
process dynamics and the nuclear structure at the scission point [2, 3]. To go a step
further in the fission characterization, our goal is to study the fission yield
dependence on the excitation energy of the compound nucleus, which is relevant for
the fission fragment treatment in stellar nucleosynthesis r-process calculations [4,5].
In order to get access to this key observable, we carried out the first quasi-free
(p,2p)-fission experiment on ²³⁸U at GSI/FAIR in 2021. The quasi-free (p,2p)
scattering collisions induce fission through particle-hole excitations that can range
from few to ten’s of MeV, and the excitation energy can be obtained by the
measurement of the two outgoing protons. In this talk we will present first results on
the yields of fragments produced in quasi-free proton scattering on 238U at 560A
MeV. These yields will be compared to state-of-the-art model calculations to derive
the excitation energy of the fissioning systems.
References:
[1] A. Chatillon et al. 2019Phys. Rev. C99054628
[2] E. Pellereau et al. 2017Phys. Rev. C95064607
[3] J.-F. Martin et al. 2015Eur. Phys. J. A51p. 174
[4] N. Vassh et al., J. Phys. G: Nucl. Part. Phys. 46, 065202 (2019)
[5] T. Kajino et al., Prog. Part. Nucl. Phys. 107, 109 (2019)

Speaker: Antia Grana Gonzalez

EUNPC2022_Antia.pdf

82 Core-breaking effects around 100Sn via lifetime measurements in the most neutron-deficient Sn isotopes.

The long Sn isotopic chain is a formidable testing ground for nuclear models aiming at describing the evolution of the shell structure. Low-lying excited states roughly exhibits the typical behavior predicted by the generalized seniority scheme. However, the corresponding B(E2; 0⁺→2⁺) values, approaching the N=Z=50 shell closure, have shown a presumed deviation from the expected parabolic behavior [1]. From a theoretical point of view, various attempts have been done to explain such experimental results, in particular by including core-breaking excitations in the shell-model calculations and promoting protons and neutrons from the g9/2 orbital across the shell gap [2]. From the experimental side, limited data are available beyond 104Sn and no lifetime information are known in this extremely neutron-deficient region, leading to a difficulty in a firm assesment of any core-breaking effects.

In this contribution, we will report recent results on lifetime measurements in 102,103Sn. The experiment was performed in May 2021 at GSI using the AIDA Si active stopper surrounded by the EUROBALL HPGe and the FATIMA LaBr3 array. The nuclei of interest were identified in the FRS separator, following the production via fragmentation reactions of a 124Xe beam on a ⁹Be target. The Sn isotopes have been stopped in the AIDA array and the decaying gamma rays collected by the FATIMA array, which allowed for a direct lifetime measurement with a precision up to few tens of ps. The analysis is ongoing and the preliminary results will be presented, together with their possible implications.

[1] G. Guastalla et al., Phys. Rev. Lett. 110, 172501 (2013); V.M. Bader et al., Phys. Rev. C 88, 051301(R) (2013); P. Doornenbal et al., Phys. Rev. C 90 (R), 061302 (2014).
[2] T. Togashi et al., Phys. Rev. Lett.121, 062501 (2018).

Speaker: Daniele Mengoni (Universita e INFN, Padova (IT))

102013Sn_lifetime_EuNPC_FINAL.pdf

P2 Nuclear Structure, Spectroscopy, and Dynamics

83 Beta-decay spectroscopy of neutron-deficient nuclei

A systematic study of neutron-deficient nuclei has been carried out by decay spectroscopy experiments with implanted radioactive ion beams (RIBs) at GANIL and RIKEN. Beta decay has a direct access to the absolute values of the Fermi and Gamow-Teller transition strengths. The comparison with complementary charge exchange reactions, such as the ($^3$He,t) reaction performed on the mirror stable targets at RCNP Osaka, allows us the investigation of fundamental questions related to the role of isospin in atomic nuclei. We have obtained remarkable results [1-5], among which the discovery of the exotic $\beta$-delayed $\gamma$-proton decay in $^{56}$Zn [1] and the first observation of the 2$^+$ isomer in $^{52}$Co [3]. These studies were extended to higher masses and more extreme nuclear conditions at RIKEN thanks to the high-intensity RIBs available. An overview of the most important results will be presented, together with the new results on $^{60}$Ge and $^{62}$Ge [5] obtained from the RIKEN experiment.
[1] S.E.A. Orrigo et al., Phys. Rev. Lett. 112, 222501 (2014).
[2] S.E.A. Orrigo et al., Phys. Rev. C 93, 044336 (2016).
[3] S.E.A. Orrigo et al., Phys. Rev. C 94, 044315 (2016).
[4] L. Kucuk, S.E.A. Orrigo et al., Eur. Phys. J. A 53 (2017).
[5] S.E.A. Orrigo et al., Phys. Rev. C 103, 014324 (2021).

Speaker: Sonja Elena Agata Orrigo (Univ. of Valencia and CSIC (ES))

Orrigo_EuNPC2022.pdf

84 In-beam γ-ray spectroscopy of $^{94}$Ag

The concept of isospin has been introduced to explain the apparent exchange symmetry between protons and neutrons. However, if the nuclear force were the same for neutrons and protons properties such as excitation energies and masses would depend only on the mass number A. Recent studies have shown that the Coulomb force cannot account for all deviations, suggesting that other isospin-symmetry-breaking components must be present. N∼Z systems present the perfect testing ground to probe isospin symmetry phenomena [1-3]. In particular, pairing correlations have a significant importance in the description of the nuclear structure of N=Z nuclei, where neutrons and protons are arranged occupying the same orbits, allowing T=0 np pairing in addition to the normal T=1. It was recently suggested that spin-aligned T=0 np pairs dominate the wavefunction of the y-rast sequence in $^{92}$Pd [4]. Subsequent theoretical studies were devoted to probe the contribution of np pairs in other N=Z A>90 nuclei [5-6], suggesting that a similar pairing scheme strongly influences the structure of these nuclei. In an effort to answer this question further, a recoil beta tagging experiment has been performed to try and identify the excited T=0 and T=1 states in odd-odd N=Z $^{94}$Ag via the $^{40}$Ca($^{58}$Ni,p3n)$^{94}$Ag reaction using MARA recoil separator and JUROGAM3 array at the Accelerator Laboratory of the University of Jyväskylä.
The detailed goals of the experiment, the setup, tentatively identified transitions, experimental CED and nuclear shell model predictions will be shown in this presentation. A preliminary interpretation of the experimental results will also be discussed.

References
[1] K. Wimmer et al., Phys. Rev. Lett. 126 (2021) 072501.
[2] R.D.O. Llewellyn et al., Phys. Lett. B 811 (2020) 135873.
[3] A. Boso et al., Phys. Lett. B 797 (2019) 134835.
[4] B. Cederwall et al., Nature 469 (2011) 6871.
[5] G.J. Fu et al., Phys. Rev. C 87 (2013) 072501.
[6] Z.X. Xu et al., Nucl. Phys. A 877 (2012) 51-58.

Speaker: Xesus Pereira-Lopez (Center for Exotic Nuclear Studies (CENS), Institute for Basic Science (IBS))

94Ag_EUNPC22.pdf

85 Shape Coexistence in Sr isotopes

The shape of nuclei is determined by a fine balance between the stabilizing effect of closed shells and the pairing and quadrupole force that tends to make them deformed. As other well known cases, located in the A = 100 mass region, as Yb, Zr or Nb for example, Sr isotopes are good candidates to study the existence of this nuclear deformation. In particular in this case, particle-hole excitations are favored because of the presence of the proton subshell closure Z = 40, resulting in low-lying intruder bands.

The aim of this contribution is the study of the nuclear structure of 92-102 Sr even-even isotopes using the Interacting Boson Model with configuration mixing to reproduce excitation energies, B(E2) transition rates, nuclear radii and two-neutron separation energies.

For the whole chain of isotopes analyzed, good agreement between theoretical and experimental values of excitation energies, transition rates, separation energies, radii and isotope shift has been found. Furthermore, the wave functions, together with the mean field energy surfaces and the value of nuclear deformation have been analyzed.

This study will clarify the presence of low-lying intruder states in even-even Sr isotopes and the way it connects with the onset of deformations. Lightest Sr isotopes considered present a spherical structure while heaviest one are clearly deformed. The onset of deformation at N = 60 is induced by the crossing of the regular and intruder configuration, furthermore, both families of states present an increase of deformation with the neutron number.

Speaker: Esperanza Maya Barbecho (Universidad de Huelva)

SR_slides_Santiago.pdf

86 Ab initio radii and density distributions for Sn and Xe isotopes

Nuclei around the tin isotopic line have been a recent center of experimental interest, with a diversity of interesting phenomena from alpha decay to neutron skin as well as neutrinoless double beta decay candidates. In the meantime, the recent progress of nuclear ab initio methods based on chiral interactions now allows for meaningful predictions in such heavy systems. We will present here results on radii and density distributions for several tin and xenon isotopes [1], and compare them to experimental results including the elastic electron scattering at SCRIT in RIKEN [2] and discuss perspectives in terms of neutron skins and the determination of the nuclear matter symmetry energy [3]. This paves the way for ab initio studies of exotic density distributions at the forefront of the present ab initio mass domain, where experimental data is becoming available.

[1] P. Arthuis, C. Barbieri, M. Vorabbi, and P. Finelli, Phys. Rev. Lett. 125, 182501 (2020)
[2] K. Tsukada, A. Enokizono, T. Ohnishi, K. Adachi, T. Fujita, M. Hara, M. Hori, T. Hori, S. Ichikawa, K. Kurita, K. Matsuda, T. Suda, T. Tamae, M. Togasaki, M. Wakasugi, M. Watanabe, and K. Yamada, Phys. Rev. Lett. 118, 262501 (2017).
[3] T. Aumann, C. A. Bertulani, F. Schindler, and S. Typel, Phys. Rev. Lett. 119, 262501 (2017)

Speaker: Dr Pierre Arthuis (Technische Universität Darmstadt)

EuNPC_Arthuis_Oct2022.pdf

P3 Nuclear Astrophysics

87 Nucleosynthesis of nuclei near the N=50 neutron shell closure

The origin of the elemental abundances from iron to uranium can be almost completely assigned to neutron capture reactions by two main stellar scenarios, each being responsible for the production of about one half of the abundances in the mass region A≥56. During explosive nucleosynthesis (occurring in supernovae events and/or neutron star mergers) short-lived and very neutron-rich nuclei are produced via the rapid neutron capture process (r process) [1].
The remaining half of the heavy elements is related to the slow neutron capture process (the s process), which produces nuclei with mass 88 ≤ A ≤ 210 during the advanced burning phases of stellar evolution [1]. Depending on the stellar mass, it operates in thermally pulsing low-mass Asymptotic Giant Branch (AGB) stars (main component) [2] or during core He and shell C burning in massive stars (weak component) [3].
The Solar System abundances of Sr, Y and Zr are relatively high. These elements are mostly synthesized by the s process in AGB stars (their production in massive stars is limited to a few percent of the total solar abundance [4]). Their abundances hence define the "ls" (light-s) s-process index routinely used to compare theoretical models to observations. The existence of this first peak is due to 88Sr, 89Y, and 90Zr, all having a magic number of neutrons (N=50), which implies that their neutron-capture cross sections are lower than those of neighbouring nuclei. As a result, they act as bottlenecks on the neutron-capture path, constraining the value of the total neutron flux necessary to proceed to the production of heavier elements up to the second s-process peak, corresponding to the next bottleneck at Ba, La, Ce, with neutron magic number of 82 (defining the heavy-s "hs" index).
Based on the characteristic features of the n_TOF facility at CERN [4], accurate measurements of the (n, ) cross sections have been performed for the 88Sr, 89Y and all stable Zr isotopes as well as for the radioactive isotope 93Zr.
In this talk the results and the implication of the new cross sections will be presented.

References
[1] E.M. Burbidge, G.R. Burbidge, W.A. Fowler, and F. Hoyle, Rev. Mod. Phs., 29 547 (1957).
[2] R. Gallino, C. Arlandini, M. Busso, M. Lugaro, C. Travaglio, O. Straniero, A. Chieffi, and M. Limongi, Ap. J. 497, 388 (1998).
[3] C.M. Raiteri, M. Busso, R. Gallino, and G. Picchio, Ap. J. 371, 665 (1991).
[4] Proposal for a Neutron Time of flight Facility, CERN-SPSC 99-8, SPSC/P 310, 17 March 1999

Speakers: Giuseppe Tagliente (Universita e INFN, Bari (IT)), Dr Giuseppe Tagliente (Universita e INFN, Bari (IT))

Enupc2022.pdf

Enupc2022.pptx

88 Neutron induced reactions and unstable nuclei: recent THM investigations at astrophysical energies

Neutron induced reactions on unstable nuclei play a significant role in the nucleosynthesis of the elements in the cosmos. Their interest range from the primordial processes occurred during the Big Bang Nucleosynthesis up to the “stellar cauldrons” where neutron capture reactions build up heavy elements. In the last years, several efforts have been made to investigate the possibility of applying the Trojan Horse Method (THM) to neutron induced reactions mostly by using deuteron as “TH-nucleus”. Here, the main advantages of using THM will be given together with a more focused discussion on the recent 7Be(n,alpha)4He and the 14N(n,p)14C reactions. The former reaction was studied via the THM application to the quasi-free 2H(7Be,aa)p reaction and it represents the extension of the method to neutron-induced reactions in which an unstable beam is present. The 14N(n,p)14C reaction was studied via the 2H(14N,p14C)p experiment performed at INFN-LNS via a 50 MeV 14N beam provided by the TANDEM accelerator. These applications open new frontiers in the application of the method (i.e. the study of 7Be+d or 11C+alpha reactions) extending its range of applicability for contributing to astrophysically relevant problems.

Speaker: Maria Letizia Sergi (UniCT & INFN-LNS)

P5 Heavy Ion Collisions and QCD Phases

89 Recent Heavy Ion Results from ATLAS and CMS

Heavy ion collisions allow access to novel QCD and QED studies in a laboratory. This opportunity is actively pursued by the ATLAS and CMS experiments at the LHC and is an integral part of the experimental program of these collaborations. Precision measurements of the properties of quark-gluon plasma (QGP) and the strong electromagnetic fields produced in heavy ion collisions at high energies are among recent research pursuits. This talk will present highlights from ATLAS and CMS on various QGP and QED probes, such as jets, electroweak bosons, heavy flavor hadrons, quarkonia, and leptons.

Speaker: Olga Evdokimov (University of Illinois at Chicago (US))

2022_EuNPC_Evdokimov_final.pdf

90 LHCb highlights in heavy ion collisions

Studies of heavy ion collisions shed light on dense QCD systems and non-perturbative effects such as gluon saturation in nuclei, deconfinement, and hadronization mechanism in the medium. The LHCb collaboration has been developing a full heavy ion program studying dense QCD medium that utilizes both fixed-target and beam-beam collisions. Thanks to the forward instrumentation of the LHCb spectrometer, data taken with both collision configurations can probe unique kinematic regions at small and large Bjorken-x in detail. The precise vertexing and full particle identification allow a wide variety of hadron species to be reconstructed down to very low transverse momentum. The fixed-target configuration covers an unexplored energy range that lies between the SPS and the top RHIC energy.

We present new LHCb results from both beam-beam and fixed-target collisions, including nuclear modification at low Bjorken-x, heavy quark hadronization in small and large systems, charm production in fixed-target collisions, and charmonium photoproduction in ultraperipheral PbPb collisions.

Speaker: Samuel Belin (Universidade de Santiago de Compostela (ES))

euNPC_samuel_belin.pdf

91 Highlights from the PHENIX experiment at RHIC

The talk will discuss recent measurements, in particular highlights about small and large collision systems, in terms of collectivity, direct photons, jets, strangeness and heavy flavor.

Speaker: Mate Csanad (Eotvos University, Budapest)

csanad_phenix_eunpc2022.pdf

92 Highlights from the heavy-ion program of the STAR and BRAHMS experiments at RHIC

Relativistic Heavy Ion Collider (RHIC) is a versatile machine for studying the properties of matter created in high-energy nuclear reactions. RHIC provides collisions of various ion beam species over a wide range of energy. Therefore, it facilitates the investigation of properties of the system with quark and gluon degrees of freedom (the Quark-Gluon Plasma, QGP) and phase transition from the ordinary nuclear matter to the QGP, thus mapping the QCD phase diagram.

This talk will present the recent highlights from the heavy-ion programs of the STAR and BRAHMS experiments at RHIC.

Speaker: Daniel Kikola (Warsaw University of Technology (PL))

STAR-BRAHMS-EuNPC2022.pdf

P8 Nuclear Physics Applications

93 Non-conventional applications of Accelerator Mass Spectrometry systems at CNA

In this talk, we will start presenting the infrastructure available at the Centro Nacional de Aceleradores to perform Accelerator Mass Spectrometry. This infrastructure is based on a 1 MV Tandetrom system used for the determination of minute amounts of long-lived cosmogenic and artificial radionuclides in a great variety of matrixes and a compact system called Micadas designed and used exclusively for 14C determination, due to the high demand of measurements of this radionuclide mainly with dating purposes.
After a presentation of the most conventional research lines followed using this infrastructure, related mostly with environmental applications, and after an evaluation of the state of the art of the technique in the centre in relation with the main AMS centres over the world, our efforts will be concentrated in to show the results achieved developing two unconventional applications of these AMS systems: a) the determination of long-lived artificial radionuclides in complex matrixes resulting from the decommissioning of commercial nuclear reactors at levels not reached with conventional radiometric methods (essential for a proper disposal assessment of the generated residues), and b) the use of 14C in some forensics studies such as the performed ones fighting against the illegal traffic of ivory pieces or fighting against the fraud in the marketing of biofuels.

Speaker: Rafael Garcia-Tenorio (Centro Nacional de Aceleradores, Sevilla, Spain)

94 Prompt-gamma measurements of 18O as contrast agent for proton range verification

Although proton therapy is advantageous over more traditional radiotherapy from the point of view of dose delivery and sparing of organs at risk, its full potential has not been reached yet [1]. A lot of effort is focused on proton range verification techniques to improve dose localization. Several of these techniques profit from secondary emissions induced by protons to determine the proton range and to estimate the dose deposited in patients [2]. They include the generation and detection of PET radioisotopes, and the production of prompt gammas (PG) by proton-induced reactions. It is therefore crucial to have reliable cross section values of the reaction channels leading to the production of the most suitable PET and PG isotopes.

The radiation induced on natural tissues is not always the most suitable to perform proton range verification. Thus, the use of contrast agents that provide an increased induced radioactivity near the Bragg peak region has been suggested to improve the range verification capabilities [3,4]. Furthermore, in the specific case of PG, inducing low energy gamma-rays (1-2 MeV) could help to improve the proton range estimation. Our studies show several promising candidates.

Water-18 (H218O) has a great potential as a contrast in PG emission for or proton range verification thanks to the oxygen 18O isotope, due to the presence of intense and low energy, discrete γ-rays. We have performed measurements of PG production at low energies at CMAM [5] in the energy range 1–10 MeV using a set-up consisting of two pairs of collinear LaBr3(Ce) detectors and a fully digital acquisition system with high-rate capabilities. We will report results of 3 discrete γ-rays coming from the irradiation 18O with protons and its angular distribution with respect to the beam direction. This data will allow us to study the feasibility of water-18 as a contrast agent in proton therapy.

[1] Knopf, A., Lomax, A., Phys. Med. Biol. 58 (15), R131, 2013.
[2] H. Paganetti, Phys. Med. Biol. 57 (11), R99, 2012.
[3] L.M. Fraile et al., Nucl. Instrum. Methods A 814, 110–116, 2016.
[4] PRONTO-CM, 2020. Protontherapy and Nuclear Techniques for Oncology.
[5] A. Redondo-Cubero et al., Eur. Phys. J. Plus, 136:175, 2021.

Speaker: VICTOR VALLADOLID ONECHA (Grupo de Fisica Nuclear (GFN) & IPARCOS, Universidad Complutense de Madrid (UCM))

eunpc_2022_vvo_v2.pdf

95 New nuclear data for online and offline PET monitoring in proton therapy

In proton therapy, Positron Emission Tomography (PET) range verification, which is based on the detection of the short-lived (online monitoring) or the long-lived (offline monitoring) $\beta^{+}$ emitters produced in the body of the patient, has been proved to be a well-suited technique to monitor the beam range [1]. This technique requires the comparison of the observed activity distribution with a simulated one using a Monte Carlo code. As the reliability of the simulated activity distribution depends on the accuracy of the underlying cross sections for producing the $\beta^{+}$ emitters of interest [2][3][4], several studies confirm the need for more and better measurements and evaluations [4][5}[6]. Indeed, new data related to the production of the short-lived nuclides involved in real-time verification [7][8][9] are especially needed, as there are no data available yet in the energy range of interest, up to 200 MeV.

The objective of this work is to measure the production cross sections of the mentioned long-lived ($^{11}$C with t$_{1/2}$ = 20.4 min, $^{13}$N with t$_{1/2}$ = 9.97 min and $^{15}$O with t$_{1/2}$ = 122 s) and short-lived ($^{12}$N with t$_{1/2}$ = 11 ms, $^{29}$P with t$_{1/2}$ = 4.14 s and $^{38mK}$ with t$_{1/2}$ = 924 ms) $\beta^{+}$ emitters. In order to measure the long-lived $\beta^{+}$ emitters, the multifoil activation technique combined with dynamic PET scanner imaging performed outside the irradiation room is applied. The technique has been first validated at the 18 MeV cyclotron of CNA in Spain [10], and then applied up to a nominal proton beam energy of 200 MeV at the WPE and HIT clinical facilities in Germany [11]. In order to measure the short-lived isotopes, single-foil irradiations with online monitoring using LaBr$_{3}$ detectors have been performed at HIT. The results from both experimental campaigns will be presented and the relevance of the new data for PET range verification will be discussed.

Speaker: Teresa Rodríguez González (Universidad de Sevilla (ES))

Thursday 27 October

Plenary Talks

96 Constraints on the nuclear Equation of State from heavy ion reaction dynamics

Recent results connected to nuclear collision dynamics, from low up to intermediate energies, will be reviewed.
Direct reactions can carry important information on yet unknown aspects of the nuclear effective interaction, relating to the excitation of isospin and spin-isospin modes.
Dissipative heavy ion reactions offer the unique opportunity to probe the complex nuclear many-body dynamics and to explore, in laboratory experiments, transient states of nuclear matter under several conditions of density, temperature and charge asymmetry. Transport models are an essential tool to undertake the latter investigations and make a connection between the nuclear effective interaction and sensitive observables of experimental interest.
In this talks, I mainly focus on the description of a selection of reaction mechanisms, also considering comparisons of predictions of different approaches. This analysis can help understanding the impact of the interplay between mean-field and correlation effects, as well as of in-medium effects, on reaction observables, which is an essential point also for extracting information on the features of the nuclear effective interaction and on the nuclear Equation of State.

Speaker: Dr Maria Colonna

EuNPC_Colonna_last.pdf

EuNPC_Colonna_last.pptx

97 Present status of the theoretical description of low energy nuclear structure.

There are two fundamental kinds of excitation modes in the atomic nucleus: collective and single-particle excitations. So far, most of the theoretical effort has focused on the study of the former and the latter has been mostly treated by using the quasiparticle spectrum of neighboring nuclei [1] or the equal-filling approximation [2]. However, these approaches explicitly neglect time-odd fields that can modify in a substantial way the properties of excited states. In order to take them into account, the Hartree- Fock- Bogoliubov (HFB) method with full blocking has to be introduced. The implementation has to be flexible enough as to allow for one-quasiparticle excitations (odd and odd-odd nuclei), two quasiparticle excitations (built on top of both even and odd systems), four quasiparticle excitations (as to study high K isomers), etc. Also, a careful handling of the orthogonality of the different states has to be made in order to obtain an excitation spectrum containing more than one state per quantum number.

In order to study those multiquasiparticle excitations a computer code has been developed to solve in an efficient way the HFB equation with full blocking in the case of the Gogny force [3]. It preserves axial symmetry so that K is a good quantum number. Parity is allowed to break but it turns out that most of the solutions only have a slight breaking of reflection symmetry and therefore the parity quantum number can also be used to characterize the states. The code includes the possibility to impose orthogonality constraints to previously computed states. The results obtained show differences with respect to simpler calculations [1,2] that can amount to a few hundred keV in excitation energy, showing the importance of the time-odd fields and the self-consistency of the HFB+Blocking method. Also the quenching of pairing correlations is very strong in the HFB+Blocking method representing a source for the reduction of the excitation energy as compared to simpler calculations.

Using the HFB+Blocking method along with the finite range, density dependent Gogny force, we have carried out calculations of high-K two and four- quasiparticle isomeric states in even-even and odd-A nuclei. The quite good agreement with experimental data for excitation energies shows the suitability and predictive power of the Gogny force in the study of this kind of physics.

One of the most important consequences of blocking is the severe quenching of pairing correlations. This effect points to an increasing relevance of dynamics pairing in those affected excitations. To gain some understanding on this effect, we have analyzed the sensitivity of the results to the amount of pairing correlations by using larger pairing strengths. The results will also be discussed.

REFERENCES
[1] T. Duguet, P. Bonche, P.-H. Heenen, and J. Meyer, Phys. Rev. C 65, 014310 (2001)
[2] S. Perez-Martin and L. M. Robledo, Phys. Rev. C 78, 014304 (2008)
[3] L. M. Robledo, R. Bernard, and G. F. Bertsch, Phys. Rev. C 86, 064313 (2012)

Speaker: Prof. Luis Miguel Robledo (Universidad Autonoma de Madrid)

Santiago.pdf

98 Nuclear fission at storage rings

Nuclear fission is a rich laboratory for studying structural, dynamical and statistical properties of nuclei. It is also highly relevant for understanding the origin of heavy elements in stars. In addition, fission is a powerful source of energy and therefore also very important for industry and society.

One of the most important fission quantities is the fission barrier as it defines the fission probability. The most direct way (and often the only way) to obtain fission barriers is to measure the fission probability as a function of the excitation energy of nuclei formed by transfer and inelastic scattering reactions. In [1] we have shown that the measurement of the fission probability together with the probabilities for the de-excitation channels that compete with fission (i.e. gamma or neutron emission) sets strong constraints to the description of the de-excitation process and can lead to a significant reduction of the uncertainty of the fission barrier parameters. However, the measurement of gamma- or neutron-emission probabilities in standard experiments is very difficult due to the very low detection efficiencies for gamma rays and low-energy neutrons. Moreover, so far decay probabilities have only been measured for nuclei close to the valley of stability due to the difficulty to produce and handle radioactive targets.

The NECTAR (NuclEar reaCTions At storage Rings) project aims to circumvent these problems by performing measurements in inverse kinematics at storage rings. The inversion of the kinematics makes possible the study of short-lived nuclei and the detection of the beam-like residues produced after neutron and gamma-ray emission with high efficiencies. The long-standing issues related to the interaction of a heavy ion beam and a thick target can be solved by using a storage ring. Indeed, in a storage ring, heavy, radioactive ions revolve at high frequency passing repeatedly through an electron cooler, which will greatly improve the beam quality and restore it after each passage of the beam through the internal gas-jet serving as ultra-thin, windowless target. This way, excitation energy and decay probabilities can be measured with unrivaled accuracy.

In this contribution, I will present the NECTAR project whose aim is to measure for the first time simultaneously fission, neutron and gamma-ray emission probabilities at the storage rings of the GSI/FAIR facility. I will also present the first results of the proof of principle experiment, which we have performed in June 2022 at the ESR storage ring of GSI/FAIR. Finally, I will discuss the short- and long-term perspectives for the study of fission at storage rings.

[1] R. Pérez Sánchez, B. Jurado et al., Phys. Rev. Lett. 125 (2020) 122502

Acknowledgment: This work has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (ERC-Advanced grant NECTAR, grant agreement No 884715).

Speaker: Beatriz JURADO APRUZZESE (LP2I Bordeaux)

jurado_eunpc2022_short.pdf

10:15 Coffee Break

Plenary Talks

99 Heavy Ions Theory Review

I will review the theoretical status of heavy ions at collider energies with especial attention to those aspects more phenomenological relevant for the CERN Large Hadron Collider. The new advances in the understanding of thermalization, the properties of the produced quark gluon plasma or the relevant of hard processes as jets or quarkonia will be considered both for large and small systems.

Speaker: Carlos Albert Salgado Lopez (Universidade de Santiago de Compostela (ES))

EuNPC2022.pdf

100 An overview of recent results from heavy-ion experiments

One of the major areas of high-energy physics is the study of nuclear matter under extreme conditions. At high temperatures and/or high net-baryon densities, a state of strongly-interacting matter, the quark–gluon plasma (QGP), in which quarks and gluons are no longer confined in hadrons, is formed. This state of matter existed just a few microseconds after the Big Bang and might exist in the core of neutron stars. The study of the properties of the QGP as well as the nature of the transition from the ordinary hadron gas phase to the QGP allows us to gain a deeper understanding of the strong nuclear force, described by quantum chromodynamics. Heavy-ion collisions at varying beam energies provide us access to large regions of the phase diagram of strongly-interacting matter. In this overview, a selection of recent results from heavy-ion experiments at the LHC, RHIC and lower energies will be discussed.

Speaker: Yvonne Chiara Pachmayer (Ruprecht Karls Universitaet Heidelberg (DE))

Pachmayer_EuNPC2022.pdf

101 Upgrades and perspectives of heavy-ion experiments

Experiments based on ultra-relativistic collisions of heavy ions are pursued in several facilities. At CERN, all large experiments at the Large Hadron Collider (LHC) participate in the heavy-ion programme and also plan corresponding upgrades. Further experiments are carried out and planned at the Super Proton Synchrotron (SPS). At RHIC, data taking with sPHENIX will commence shortly. At FAIR, the CMB collaboration prepares a detector for installation at the SIS-100 accelerator. In this presentation, we will review the plans for the upgrades and the perspectives for heavy-ion physics at different stages.

Speaker: Jochen Klein (CERN)

2022-10-27-EuNPC-UpgradesHI-jkl.pdf

102 A new experiment to measure Parity violation in trapped chiral molecular ions

The weak interaction is predicted to give rise to slightly different structures for left and right-handed chiral molecules, contrary the common conception that enantiomers are perfect mirror images. The consequences range from the nulling of the tunnelling rate in chiral molecules to a possible seed of homo-chirality in the chemistry of life. We are building a new experiment aimed at observing parity violation (PV) in molecules for the first time. We will use charged chiral molecules which can be easily trapped and have unique pathways to prepare internally cold molecules. Toward our goal we have developed a novel method to differentially extract the PV signature from a racemic sample, overcoming the need to synthesize samples of a single handedness to be measured separately. The differential nature of the scheme enables common-mode noise rejection for signal of interest, optimizing the precision and minimizing susceptibility to systematic shifts.
This experiment may turn into a platform to test fundamental physics and search for beyond Standard Model physics.

[1] Itay Erez, Eliana Ruth Wallach and Yuval Shagam arXiv:2206.03699 (2022)

Speaker: Yuval Shagam (Technion)

ShagamEuNPC_v3.pdf

ShagamEuNPC_v3.pdf

ShagamEuNPC_v3.pptx

13:00 Lunch Break

Poster Session + Coffee

P2 Nuclear Structure, Spectroscopy, and Dynamics

103 The role of pear shape deformation on the fission of actinides and in the mercury region

Nuclear fission of heavy (actinide) nuclei results predominantly in asymmetric mass-splits. Without quantum shells, which can give extra binding energy to these mass-asymmetric shapes, the nuclei would fission symmetrically. The strongest shell effects are in spherical nuclei, so naturally, the spherical "doubly-magic" 132Sn nucleus, was expected to play a major role.

However, systematic studies of fission have shown that the heavy fragments are distributed around Z=52 to 56, indicating that 132Sn is not the only driver. Reconciling the strong spherical shell effects at Z=50 with the different Z values of fission fragments observed in nature has been a longstanding puzzle. Here, we show that the final mass asymmetry of the fragments is determined by the extra stability of octupole (pear-shaped) deformations which have been recently found experimentally around 144Ba (Z=56), one of the very few nuclei with shell-stabilized octupole deformation. Using a modern quantum many-body model of superfluid fission dynamics, we found that heavy fission fragments are produced predominantly with 52-56 protons, associated with significant octupole deformation acquired on the way to fission. These octupole shapes favoring asymmetric fission are induced by deformed shells at Z=52 and 56 [1]. In contrast, spherical "magic" nuclei are very resistant to octupole deformation, which hinders their production as fission fragments.

These findings also explain surprising recent observations of asymmetric fission of lighter than lead nuclei. Such as the discovery that 180Hg fission is mass asymmetric instead of being symmetric with two semi-magic 90Zr fragments [2]. To test the universality of the octupole effect on fission, we investigate with the constraint Hartree-Fock + BCS approach the effect of quadrupole and octupole deformations on the fission asymmetry of elements around 180Hg. The density at the scission as well as the neutron localisation function from which quantum shell signatures can be investigated show clearly an octupole deformation of the fragments[3].

[1] G. Scamps and C. Simenel, Nature 564, 382–385 (2018).
[2] A. N. Andreyev, Phys. Rev. Lett. 105, 252502 (2010).
[3] G. Scamps and C. Simenel, Effect of shell structure on the fission of sub-lead nuclei, Phys. Rev. C 100, 041602(R) (2019).

Speaker: Guillaume Scamps (University of washington)

presentation.pdf

104 Fission hindrances in transfermium nuclei

Very heavy nuclei owe their stability against spontaneous fission to quantum shell effects, which depend on the local density of single-particle states. High densities give rise to positive shell correction, meaning less stability and low densities translate into enhanced stability. Alternating stabilising effects may coexist on the pathway to scission as a function of deformation. In $^{254}$No, the net result is a potential-energy barrier against fission of the order of 6.6 MeV while the liquid drop value is $\sim$0.9 MeV [1]. The height but also the width and the structure of the barrier in multi-dimensional deformation space determine the fission half-lives. Other effects come into play, such as the conservation of quantum numbers (specialization energy) and superfluidity or stiffness of the system in the fission process. This is why odd nuclei have longer fission partial half-lives with respect to their even neighbours and also why multi-quasi-particle states such as high-$K$ states are thought to be more stable against fission than the ground state. On behalf of the GABRIELA collaboration, I will report here on two different fission studies carried out with the GABRIELA [2,3] detector array at the focal plane of the recoil separator SHELS [4]. The first study concerns the fission properties of $^{253}$Rf, the most neutron deficient Rf isotope known to date, where two low-lying fissioning states have been recently observed [5,6]. The second study focusses on new measurements of the fission hindrance of known high-$K$ isomers in even No isotopes.

[1] G. Henning et al., Phys. Rev. Lett. 113, 262505 (2014)
[2] K. Hauschild et al., Nucl. Instr. Meth. A 560 (2006) 388-394
[3] R. Chakma et al., Eur. Phys. J. A 56 (2020) 245
[4] A. Popeko et al., Nucl. Instr. Meth. B 376 (2016) 140
[5] J. Khuyagbaatar et al., Phys. Rev. C 104, L031303 (2021)
[6] A. Lopez-Martens et al., Phys. Rev. C 105 (2022) L021306

Speaker: Araceli LOPEZ-MARTENS (IJCLab)

Santiago_Lopez.pdf

Santiago_Lopez.pptx

105 Experimental results of high-energy fission and quasi-fission dynamics with fusion-induced fission reactions at VAMOS++

During the last ten years, the use of inverse kinematics in the experimental study of fission is bringing a wealth of new observables obtained in single measurements, which allows their analysis and, also importantly, of their correlations [1, 2]. An ongoing application of this technique the basis of a series of experiments performed with the variablemode, large-acceptance VAMOS++ spectrometer at GANIL (France) [3, 4]. In these experiments, fission reactions are induced by fusion and transfer reactions between a 238U beam and a set of different light targets. The kinematics of the transfer and fusion reactions allows us to identify the fissioning system and determine its initial excitation energy [5], while the data from the VAMOS spectrometer gives us the isotopic identification for the full fragments distribution, and their velocity vectors. These measurements result in an accurate determination of the fragments mass before and after post-scission neutron evaporation, their neutron multiplicity, the total kinetic and excitation energy, and their emission angle in the centre of mass [1, 6, 7]. In addition, these characteristics can be studied as a function of the initial excitation energy of the fissioning system [9]. The correlation between these magnitudes also permits to determine, for instance, the scission configuration and the sharing of excitation energy between the fragments [8, 9], and even to obtain information about the balance between intrinsic and collective excitation energy [10].

In a recent experiment, we have focused on the survival of nuclear structure effects in high excitation energy and the frontier between fission and quasi-fission. The main objective is to build and to study observables that would allow us to estimate the fission and quasi- fission components of the production and to identify relevant shells, such as newly highlighted octupolar-deformed closed shells [11], and their role on the fission dynamics at high energy.

The results of our analysis show that the ratio between neutrons and protons at scission as a function of the fragment split, together with the total kinetic and excitation energies, and the isotopic yields, reveal the presence of structure effects related at high energy, even if pre scission evaporation is taken into account.

Concerning the quasi-fission component, the classical mass-angular distribution is completed in our case with the fragment identification, the ratio between neutrons and protons, and more importantly, the ratio between the production of fragments with an even and odd number of protons, the so-called even-odd effect [12, 13]. The latter shows a clear different mechanism for fission and quasi- fission that can be used to address, not only the separation between fission and quasi-fission, but also to study the energy dissipated in each of these processes.

[1] M. Caamaño et al., Phys. Rev. C 88, 024605 (2013)
[2] E. Pellereau et al., Phys. Rev. C 95, 054603 (2017)
[3] S. Pullanhiotan, et al., Nucl. Instr. and Meth. A 593, 343 (2008)
[4] M. Rejmund et al., Nucl. Instr. and Meth. A 646, 184 (2008)
[5] C. Rodr  guez-Tajes et al., Phys. Rev. C 89, 024614 (2014)
[6] D. Ramos et al., Phys. Rev. C 99, 024615 (2019)
[7] D. Ramos et al., Phys. Rev. Lett. 123, 092503 (2019)
[8] M. Caama~no et al., Phys. Rev. C 92, 034606 (2015)
[9] D. Ramos et al., Phys. Rev. C 101, 034609 (2020)
[10] M. Caama~no and F. Farget, Phys. Lett. B 770, 72 (2017)
[11] G. Scamps and C. Simenel, Nature 564, 382 (2018)
[12] B. Jurado and K.-H. Schmidt, J. Phys. G 42, 055101 (2015)
[13] D. Ramos et al., to be published

Speaker: Daniel Fernandez Fernandez (Universidade de Santiago de Compostela (ES))

106 Fission decay modes of 254Fm* compound nucleus formed in 16O+238U reaction

A thorough understanding of nuclear fission is still an arduous task due to its sudden transition from asymmetric to symmetric division, especially in the actinide mass region (near A=254 to 258). Recently, an attempt has been made to see the effect of compact and elongated configurations of quadrupole (β2) deformed decay fragments on the spontaneous fission of 242-260Fm isotopes using preformed cluster model [1]. It has been observed that tip-to-tip (elongated) configuration results in the production of double-peaked (asymmetric) to triple-humped (multimodal) fission fragment mass distribution with an increase in neutron number of Fm isotopes. In the present work, Quantum mechanical fragmentation theory (QMFT) [2] based dynamical cluster-decay model (DCM) [3] is applied to analyze the possibility of multimodal fission modes of excited 254Fm compound nucleus produced in 16O+238U nuclear reaction. The calculations are made at center-of-mass energy Ec.m.≈ 84 MeV near the Coulomb barrier by considering T-dependent β2-deformed compact as well as elongated configurations with optimum orientations. The competitive emergence of different symmetric [symmetric superlong (SL), symmetric supershort (SS)] and asymmetric [standard 1 (S1), standard 2 (S2), standard 3 (S3), superasymmetric (SA)] fission modes has been explored by studying the fragmentation potential and multi-humped peak of preformation yield P0 of 254Fm. The division of mass and charge in nuclear fission of 254Fm* depicts the importance of spherical and deformed magic shell closures. The most energetic light (AL) and heavy (AH) decay fragments of aforementioned fission modes are identified. Moreover, the DCM-calculated fission cross-section and other depicted results show reasonable agreement with the experimental measurements of Ref. [4].

1. A. Kaur, N. Sharma and M. K. Sharma, Phys. Rev. C 103, 034618 (2021).
2. R. K. Gupta, W. Scheid, and W. Greiner, Phys. Rev. Lett. 35, 353 (1975).
3. B. B. Singh, M. K. Sharma, and R. K. Gupta, Phys. Rev. C 77, 054613 (2008).
4. T. Banerjee et al., Phys. Rev. C 105, 044614 (2022).

Speaker: Dr Amandeep Kaur (Department of Physics, Faculty of Science, University of Zagreb, Bijenička c. 32, 10000 Zagreb, Croatia)

EuNPC2022_Amandeep.pdf

EuNPC2022_Amandeep.pptx

107 Study of (p,2p) at CALIFA calorimeter in knockout induced fission of 238U

Nuclear fission has been used as a tool for the study of nuclear properties since its discovery in 1939. A new approach was performed in the context of the R3B collaboration, at the FAIR facilities, in which knockout reactions were used to induce fission in $^{238}$U, that will allow to characterise the excitation energy of the process. The CALIFA calorimeter, a key part of the set-up, will be used to reconstruct the momentum of the two protons coming out the $(p,2p + f)$ reaction. Preliminary results show that kinematic variables and quasifree regime are well reconstructed and in good agreement with theory.

Speaker: GARCIA JIMENEZ GABRIEL Not Supplied

Gabriel_Garcia_Knockout_Fission_EUNPC .pdf

108 Fragmentation-induced fission reactions of 236U in inverse kinematics to investigate the pre-fragment angular momentum parameterizations

In the last decade, unprecedented fission experiments have been carried out at the GSI facility using the inverse kinematics technique in combination with state-of-the art detectors, especially designed to measure the fission products with high detection efficiency and acceptance [1,2]. For the first time in the long-standing history of fission, it was possible to simultaneously measure and identify both fission fragments in mass and atomic numbers and obtain many correlations among them sensitive to the fission dynamics [1,3] and the nuclear structure at the scission point [4,5]. In this talk I will show the results obtained during the 2014 experimental campaign at GSI, in which fragmentation reactions were used to induce fission on 236U at kinetic energies around 700A MeV. The yields of the fissioning systems and the widths of the fission fragment charge distributions will be used to investigate the effects introduced by the angular momentum gained by the pre-fragment or compound nucleus. Our findings indicate that the current parameterizations used to calculate the angular momentum gained by the pre-fragment after the abrasion process [6] would work for the description of fragmentation nuclear residues, but underestimate the angular momentum for fission reactions. Therefore, those parameterizations will need to be improved in future theoretical developments.

[1] J. L. Rodríguez-Sánchez et al., Phys. Rev. C 91 (2015) 064616
[2] E. Pellereau et al., Phys. Rev. C 95 (2017) 054603
[3] J. L. Rodríguez-Sánchez et al., Phys. Rev. C 96 (2016) 061601(R)
[4] A. Chatillon et al., Phys. Rev. Lett. 124 (2020) 202502
[5] A. Chatillon et al., Phys. Rev. C 99 (2019) 054628
[6] J.-J. Gaimard, K.-H. Schmidt, Nucl. Phys. A 531 (1991) 709

Speaker: Jose Luis Rodriguez Sanchez (University of Santiago de Compostela)

Presentation_EuNPC2022.pdf

P4 Astroparticle Physics

109 Recent results from Borexino on solar neutrinos

Borexino has been a solar neutrino detector based on 280 tons of ultrapure liquid scintillator, located at the Laboratori Nazionali del Gran Sasso, Italy. Its main scientific goal was the real-time measurement of solar neutrino fluxes, which play an irreplaceable role for the comprehension of the mechanisms powering our star.
In the earlier data taking stage, Borexino completed the spectroscopy of the solar neutrinos emitted from the primary pp chain reactions. By analyzing the 2016-2020 dataset, it also claimed the first detection of the marginal neutrinos flux from the so-called CNO reactions cycle, paving the way for a solution to the long-standing solar metallicity problem. In this sequence, the hydrogen fusion is catalysed by Carbon, Nitrogen and Oxygen: consequently, the neutrinos flux directly depends on these elements abundance in the solar core and on the metallicity scenario. Over the past two years, the Borexino collaboration has pursued the improvement of the CNO flux measurement, obtaining further indications about the solar metallicity.
This talk will cover the most recent Borexino results on solar neutrinos spectroscopy, focusing on their impact on solar physics.

Speaker: Davide Basilico

[EuNPC 2022] Recent results from Borexino on solar neutrinos-1.pdf

110 Physics at ultra-high energies: results from the Pierre Auger Observatory

The Pierre Auger Observatory is the largest cosmic ray observatory ever build- It samples the highest energy particles which travel through the interstellar medium by detecting the extensive showers they produce in the atmosphere. In this talk we will briefly review the main results of the observatory to understand the nature and origin of the ultra-high energy cosmic rays, and will concentrate on the unique opportunity to study hadronic interactions with the atmospheric nuclei, far beyond the limit of human-made accelerators.

Speaker: Lorenzo Cazon (IGFAE-USC)

LCazon Physics at ultra-high energies with the Pierre Auger Observatory.pdf

111 Detection system for muography applications - design and testing

A new detection system was designed for muography applications, based on scintillator bars and SiPM read-out. Monte-Carlo simulations were performed to evaluate detector characteristics (efficiency, acceptance, resolution) aiming for secondary muon trajectory reconstruction.
The basic unit of this detector, consisting of a scintillator bar with an optical fiber waveguide and two SiPM devices collecting the light signal at both ends of the fiber, was submitted to tests using cosmic-ray muons. The temporal resolution of this base unit was determined using the time-of-flight method. Temperature dependence of the SiPMs and uncertainties induced by the non-uniformity of the scintillator and optical fibers have also been investigated, taking into account specific requirements for muography applications.

Speaker: Raluca Smau (National Institute for Physics and Nuclear Engineering Horia Hulubei)

EUNPC_RalucaSmau.pdf

EUNPC_RalucaSmau.pptx

P5 Heavy Ion Collisions and QCD Phases

112 Features of strangeness production in pp and heavy ion collisions

Similarities between pp and A-A collisions in terms of collective type phenomena and geometrical scaling were already evidenced at the LHC energies. New systematic studies of the strangeness production dependence on the particle density per unit of rapidity and unit of transverse overlap area and comparison between pp and AA collisions will be presented.

Speaker: Prof. Mihai Petrovici (Horia Hulubei National Institute of Physics and Nuclear Engineering)

EuNPC_talk_mp.pdf

113 Study of strange particle pT spectra in heavy-ion collisions at relativistic energies

The transverse momentum distributions of identified hadrons contain information about the collective expansion and the freeze-out properties of the nuclear matter created in high-energy heavy-ion collisions. Due to different hadronic interaction cross-sections, it is assumed that different particle species freeze-out from the fireball at different times when the system has different temperatures and collective flow velocities. Boltzmann-Gibbs blast-wave model was used to analyze the pT spectra of strange hadrons (${\rm K}^{0}_{\rm{S}}$, $\rm \Lambda$, $\rm \overline{\Lambda}$, $\rm \Xi^{-}$, $\rm \overline{\Xi}^{+}$, $\phi$, $\rm \Omega^{-}$, and $\rm \overline{\Omega}^{+}$) produced in Au+Au collisions at RHIC-BES energies. The kinetic freeze-out temperature, the transverse flow velocity and the flow profile exponent will be presented and discussed as a function of collision centrality and energy. The results indicate that the strange hadrons tend to decouple earlier from the system than the bulk hadrons (charged pions, kaons, protons and antiprotons), having a smaller average transverse flow velocity. The centrality and energy dependence of the average transverse momentum of strange particles will also be presented. For peripheral Au+Au collisions, the average pT is found to scale with the reduced hadron mass, i.e., mass divided by the number of quark constituents (m/nq). The scaling is broken in most central Au+Au collisions, where, the average pT is higher for baryons than that for mesons and increases linearly with m/nq. The results will be compared with previous results from SPS and RHIC experiments.

Speaker: Oana Ristea (University of Bucharest, Faculty of Physics)

OanaRistea_EuNPC2022.pdf

114 New experimental observables to probe (anti)nucleosynthesis with ALICE

The formation of light (anti)nuclei in heavy-ion collisions as well as in hadron collisions has been studied experimentally and theoretically for many decades. Two competing (anti)nucleosynthesis models are typically used to describe light (anti)nuclei yields and their ratios to other hadrons in heavy-ion collisions: the statistical hadronization model (SHM) and the nucleon coalescence model.
In this talk, new measurements of (anti)nuclei production in Pb-Pb collisions at the LHC measured with the ALICE experiment are presented. With these measurements, spanning from (anti)deuterons to (anti-)4He, we show how (anti)nuclei can be used to measure both the chemical freeze-out temperature and the baryon chemical potential with great precision. Moreover, these measurements are compared to predictions from the state-of-the art statistical hadronization and coalescence models.
Additionally, the first measurement of event-by-event antideuteron number fluctuations in heavy-ion collisions is also presented and compared with expectations of the SHM and coalescence. This new observable represents an additional testing ground for these two production models.

Speaker: Francesco Mazzaschi (Universita e INFN Torino (IT))

eu_npc_mazzaschi_v5-2.pdf

115 Multiplicity-dependent production of heavy mesons with strangeness in small systems at LHCb

The phenomenon of strangeness enhancement, originally proposed as a signature of quark-gluon plasma formation, has received considerable new interest following recent observations in small collision systems. LHCb is uniquely well suited to study such effects in the heavy quark sector, down to very low transverse momentum. Here we will present new LHCb results on the production rates of $B_{s}^{0}$ relative to $B^{0}$ mesons and $D_{s}^{+}$ relative to $D^{+}$ mesons versus multiplicity in $pp$ and $p$Pb collisions. Potential implications for the hadronization mechanism of heavy quarks and our understanding of the factorization of fragmentation functions will be discussed.

Speaker: Clara Landesa Gomez (Universidade de Santiago de Compostela (ES))

EuNPC-Strangeness.pdf

116 First measurements of antinuclei inelastic cross sections and their impact on astrophysical dark matter searches

Space: the final frontier for antinuclei physics. There, antinucleisynthesis models already tested on the bench of hadronic colliders and particle physics experiments are put to work to crack one of the biggest problems of modern physics: the existence and nature of dark matter.

In fact, the observation of an antinucleus in cosmic rays would most probably mean a breakthrough in searches for dark matter. However, to correctly interpret future results, precise knowledge of both the antinucleis' production mechanism and their nuclear inelastic cross sections are needed.
The ALICE collaboration already investigated in detail the anti nucleosynthesis models in small and large colliding systems at the LHC and has recently performed several measurements of antideuteron, $^3\overline{\mathrm{H}}$ and $^3\overline{\mathrm{He}}$ inelastic cross sections, providing the first experimental information of this kind.

In this talk, the final results on antideuteron and $^3\overline{\mathrm{He}}$ inelastic cross-sections and the new results on antitriton inelastic cross-sections are discussed, as well as how, thanks to them, it is possible to determine for the first time the transparency of the galaxy to antinuclei stemming from dark matter and standard model collisions.

Speaker: Stephan Alexander Konigstorfer (Technische Universitaet Muenchen (DE))

P6 Hadron Structure, Spectroscopy, and Dynamics

117 Dispersive and analytic methods for light scalars. Where do we stand?

Dispersive and analytic methods have contributed to settle the longstanding debate on the existence and parameters of light scalar mesons.I will review the present situation and describe the latest developmentsin the strange sector, particularly the controversial K0(700) or kappa, as well as the f0(1370).

Speaker: Jose R. Pelaez

2022-10-27-Santiago-EuNPC2022-JRPelaez.pdf

2022-10-27-Santiago-EuNPC2022-JRPelaez.pptx

118 Extracting the nucleon axial form factor from Lattice QCD using chiral perturbation theory

The axial form factor is a fundamental property of the nucleon and a key ingredient of neutrino-nucleon cross sections. We have calculated this form factor in relativistic Chiral Perturbation Theory at next to leading one-loop order. We investigate the problem of convergence of the perturbative series and fit to recent LQCD results. The explicit Delta(1232) is crucial to reconcile the light-quark mass dependence of the axial charge with phenomenology. Moreover, the axial radius is also extracted without relying on ad-hoc parametrisations.

Speaker: Fernando Alvarado

F_A_presentation_Santiago_2022-1.pdf

119 Deeply Virtual Compton Scattering with CLAS12 at Jefferson Lab

A key step toward a better understanding of the nucleon structure is the study of Generalized Parton Distributions (GPDs). GPDs are nowadays the object of an intense effort of research since they convey an image of the nucleon structure where the longitudinal momentum and the transverse spatial position of the partons inside the nucleon are correlated. Moreover, GPDs give access, via Ji's sum rule, to the contribution of the orbital angular momentum of the quarks to the nucleon spin, important to the understanding of the origins of the nucleon spin. Deeply Virtual Compton scattering (DVCS), the electroproduction of a real photon off the nucleon at the quark level, is the golden process directly interpretable in terms of GPDs of the nucleon. The GPDs are accessed in DVCS mainly through the measurements of single- or double- spin asymmetries. Combining measurements of asymmetries from DVCS experiments on both the neutron and the proton will allow performing the flavor separation of relevant quark GPDs via linear combinations of proton and neutron GPDs. This talk will mainly focus on recent DVCS measurements from the CLAS12 experiment at Jefferson Lab with the upgraded ~11 GeV CEBAF polarized electron beam. Details on the data analysis along with results on Beam Spin Asymmetries are presented.

Speaker: Adam HOBART (IJCLab CNRS-IN2P3)

EuNPC2022_ajh.pdf

120 Deeply Virtual Compton Scattering off light nuclei: a phenomenological study

The modification of the bound nucleons’ parton structure induced by the nuclear medium, known as EMC effect, is still nowadays a hot topic. Exclusive scattering processes as deeply virtual Compton scattering (DVCS) are able to provide hints about the three-dimensional partonic structure of any hadronic system from a new point of view. Going beyond the collinear information coming from deep inelastic scattering experiments, the structure functions accessed in DVCS, the so called generalized parton distributions (GPDs), give access to the correlation between the spatial and the momentum degrees of freedom of the constituent partons.
Within this framework, the study of the hadronic structure of nuclei can be faced in two ways. In the coherent DVCS, the initial nucleus doesn't break up after the scattering with the incoming electron and the partonic structure of the whole nucleus can be entered; conversely, in the incoherent DVCS a bound nucleon is detected in the final state after the breaking up of the initial nucleus. The information coming from this latter channel can be compared with the ones well established for the free nucleon in order to shed light on some unknown aspects of the EMC effect.
In this talk, we will present phenomenological models able to describe the hadronic structure of nuclei within the GPD framework studying both DVCS channels. Light nuclei are the targets of our studies since realistic calculations accounting for phenomenological nucleon-nucleon potential and three-body forces can be made for these systems. This allows to properly describe the nuclear effects occurring in the hadronic structure of the targets.
While for the $^4$He, the numerical results of our approach have already been compared with the Jefferson Lab experimental data (for both the channels) showing interesting results, for the deuteron, whose nuclear description is easier, first results from our model will be shown in this talk.
Finally, after a description of our theoretical approach a glimpse on the phenomenological application of these studies in view of the EIC will be caught.

Speaker: Sara FUCINI (IJCLab)

eunpc22_fucini.pdf

P8 Nuclear Physics Applications

121 Radiotracers for the study of Marine and Oceanic Ecosystems (Radiotrazadores para el estudio de Ecosistemas Marinos y Oceánicos: REMO)

Since the beginning of the industrial revolution, the ocean has absorbed about one third of the carbon dioxide (CO2) released by human activity. This has led to an acidification of the oceans, which influences the physiology of aquatic organisms and, in general, the ecology of marine ecosystems. This is often called the other CO2 problem. The REMO project focuses on the study of marine species affected by acidification of waters, using radiotracers (starting with 45Ca) and nuclear instrumentation techniques to monitor the growth of mollusks and corals in simulated conditions. The novelty of the project is the non-destructive technique, allowing to observe the influence of the acidification as a function of the time, during typical periods of months or years. The project puts together the unique installations of the Valencia Oceanographic, the experience of their personnel, with the experience of marine scientist at the Institute Torre la Sal in Castellon, and of nuclear physicist at IFIC-Valencia and LNL-Legnaro-Italy.

Speaker: Prof. Berta Rubio (IFIC (CSIC-Un. Valencia) Spain)

Presentation_Santiago_indico.pdf

Presentation_Santiago_indico.pptx

122 Fast neutron-induced reaction measurements with a laser-driven neutron source

High-power lasers with ultrashort pulses are emerging as a promising alternative to conventional accelerators for the production of neutron beams. Laser-driven neutron sources (LDNS) are particularly attractive for nuclear physics applications based on the time-of-flight technique due to their short pulse and high instantaneous flux. However, the experimental conditions associated with this type of source are harsh and hence the response of the detectors commonly used for nuclear reaction measurements must be investigated.

In 2021, a study on the feasibility of nuclear reaction measurements was carried out in the complex environment of an LDNS at the DRACO laser facility of the Helmholtz Center Dresden-Rossendorf (HZDR) in Dresden, Germany, producing almost 1300 neutron shots in a high-power system in stable conditions. In addition to conventional scintillators and bubble detectors, multishot neutron production made possible to use a detector with low efficiency, i.e. diamond detector, to measure individual signals from fast neutron interactions, which is the first step towards experiments on fast neutron-induced reactions in an LDNS.

All the know-how obtained in DRACO was applied in October 2022 in a new experimental campaign at Centro de Láseres Pulsados (CLPU) in Salamanca, using the VEGA III laser facility with the objective of testing the performance of new detectors and carrying out the first neutron-induced fission cross-section measurements at a LDNS.

We report herein on both experiments, the preliminary results and the prospects for nuclear reaction measurements at LDNSs.

Speaker: Maria Angeles Millan Callado (Universidad de Sevilla (ES), Centro Nacional de Aceleradores (ES))

EuNPC2022_MAMC.pdf

EuNPC2022_MAMC.pptx

123 Beta decay studies for the calculations of the antineutrino spectrum from reactors and applications

Predicting the antineutrino spectrum from reactors is relevant for a range of applications from the study of neutrino oscillations parameters to non-proliferation. Two methods for reconstructing the antineutrino spectrum have been used in the past: the conversion method [1,2], based on the measurements of Schreckenbach and collaborators [1], the summation method [3,4] or a combination of both [4]. The comparison of the predicted spectrum with the measurements has also led to the so-called reactor anomaly [5], a problem that has attracted considerable attention in recent years.

In this contribution I will present a systematic study of beta decays of the most relevant fission products performed by our collaboration (see for example [6,7,8,9] using the total absorption technique [10,11], that has improved considerably the prediction of the antineutrino spectrum from reactors using the summation method [12].

The measurements have also impact in nuclear structure, astrophysics and practical applications as the calculations of the decay heat from nuclear reactors (see for example [8,11]).

In the contribution I will present the problems faced when calculating the antineutrino spectrum, introduce the technique used in our beta decay studies and provide examples of the studied cases and their impact in different applications.

[1] K. Schreckenbach et al., Phys. Lett. B 99, 251 (1981); K. Schreckenbach et al., Phys. Lett. B 160, 325 (1985); F. von Feilitzsch, A.A. Hahn, K. Schreckenbach, Phys. Lett. B 118, 162 (1982); A.A. Hahn et al., Phys. Lett. B 218, 365 (1989)
[2] P. Huber, Phys. Rev. C 84, 024617 (2011)
[3] T.A. Mueller et al., Phys. Rev. C 83, 054615 (2011)
[4] M. Fallot et al., Phys. Rev. Lett. 109, 202504 (2012);
[5] G. Mention et al., Phys. Rev. D 83, 073006 (2011)
[6] A. Algora et al., Phys. Rev. Lett. 105, 202501 (2010); D. Jordan et al., Phys. Rev. C 87, 044318 (2013).
[7] A. A. Zakari-Issoufou et al., Phys. Rev. Lett. 115, 102503 (2015).
[8] J. L. Tain et al., Phys. Rev. Lett. 115, 062502 (2015); E. Valencia et al., Phys. Rev. C 95, 024320 (2017).
[9] V. Guadilla et al., Phys. Rev. Lett. 122, 042502 (2019)
[10] B. Rubio et al., J. Phys. G Nucl. Part. Phys. 31, S1477 (2005)
[11] A. Algora et al., Eur. Phys. J. A 57 (2021)
[12] M. Estienne et al., Phys. Rev. Lett. 123, 022502 (2019).

Speaker: Dr Alejandro Algora (IFIC (CSIC-Univ. of Valencia) and ATOMKI)

124 Neutron spectrometry with HENSA in underground facilities and neutrons induced by cosmic-rays

Neutrons are produced in underground facilities from nuclear reactions induced by the intrinsic radioactivity of the materials in the rock and cavity walls. These radiogenic neutrons constitute a background which is a limiting factor for underground physics, in particular low counting rate experiments in nuclear astrophysics, dark matter and neutrino searches. On the other hand, neutrons are continuously produced as a secondary radiation from cosmic-ray interactions in the upper atmosphere of our planet. This component is the main contribution to the ambient neutron background observed at ground level or high altitudes. Cosmic-ray induced neutrons are connected with different fields such as environmental radioactivity, single event upsets (SEUs) in microelectronics, and space weather.
The High Efficiency Neutron Spectrometry Array (HENSA) is a state-of-the-art detection system for neutron spectrometry in low radioactivity facilities, such as underground laboratories, and for the measurement of secondary neutrons produced by cosmic-rays. HENSA has a spectral sensitivity 5-15 times larger than conventional neutron spectrometers in the energy range spanning from thermal up to several GeV.
In this contribution the HENSA project (www.hensaproject.org) will be introduced. The experimental activities in underground laboratories will be outlined, including a recent background measurement at the Dresden Felsenkeller underground facility and the long-term characterization of the neutron background at the Canfranc Underground Laboratory (LSC). The use of HENSA for measurements of cosmic-ray neutrons will be also presented, in particular, preliminary results from a mapping of the cosmic-ray neutron background along the spanish territory, during quiet solar conditions, just at the beginning of the solar cycle #25. Prospects with HENSA in astroparticle physics and space weather will be also discussed.

Speaker: Mr Nil Mont-Geli (Institut de Tècniques Energètiques (INTE), Universitat Politècnica de Catalunya (UPC), E-08028 Barcelona, Spain)

Atarifeno_NMont_EuNPC_HENSA.pdf

125 Nuclear fragmentation cross section measurements with the FOOT experiment

Hadrontherapy employs high-energy beams of charged particles (protons and heavier ions) to treat deep-seated tumours: these particles have a favourable depth-dose distribution in tissue characterized by a low dose in the entrance channel and a sharp maximum (Bragg peak) near the end of their path.
Moreover, Carbon and Oxygen ions have an enhanced biological effect allowing to successfully treat radioresistant tumours.
In these treatments nuclear interactions have to be considered: beam particles can fragment in the human body releasing a non-zero dose beyond the Bragg peak while fragments of human body nuclei can modify the dose released in healthy tissues. These effects are still in question given the lack of interesting cross section data.

Also space radioprotection can profit by fragmentation cross section measurements: the interest in long-term manned space missions beyond Low Earth Orbit is growing in these years but it has to cope with major health risks due to space radiation.
To this end, risk models which are highly dependent on underlying physical models are under study: however, huge gaps in fragmentation cross section data are currently present preventing an accurate benchmark of deterministic and Monte Carlo codes.
To fill these gaps in data, the FOOT (FragmentatiOn Of Target) experiment
was proposed. It is composed of two independent and complementary setups, an Emulsion Cloud Chamber and an electronic setup composed by several subdetectors providing redundant measurements of kinematic properties of fragments produced in nuclear interactions between a beam and a target. FOOT was designed to detect, track and identify nuclear fragments and aims to measure double differential cross sections both in angle and kinetic energy which is the most complete information to address existing questions.
The FOOT experimental setups, the experimental program and a first cross section analysis of $400$ MeV/u $^{16}$O beam on Carbon target data acquired in July 2021 at GSI (Darmstadt, Germany) will be presented.

Speaker: Riccardo Ridolfi

ridolfi_EUNPC22.pdf

P9 Few-Body Systems

126 Few Body Reactions with the Trojan Horse Method

The Trojan Horse method (THM) is a well-established experimental technique to measure nuclear reactions of astrophysical interest avoiding the suppression of the Coulomb barrier affecting experimental direct measurements.
I will describe some of the THM studies involving few-body system of interest for both nuclear physics and nuclear astrophysics, such as the sub-Coulomb proton-proton elastic scattering and the deuteron-deuteron fusion at energies of interest for primordial nucleosynthesis. Moreover, the role of the intercluster motion in nuclei used for THM measurement will be highlight for the discussed physics cases.
Finally, I will highlight new perspectives with the THM applied to few-body systems.

Speaker: Giuseppe Gabriele Rapisarda

127 Extending the Hoyle-state paradigm to $^{12}$C + $^{12}$C fusion

Carbon burning is a key step in the evolution of massive stars, Type 1a supernovae and superbursts in x-ray binary systems. Determining the $^{12}$C+$^{12}$C fusion cross section at relevant energies by extrapolation of direct measurements is challenging due to resonances at and below the Coulomb barrier. A study of the $^{24}$Mg($\alpha$,$\alpha$')$^{24}$Mg reaction has identified several 0$^{+}$ states in $^{24}$Mg, close to the $^{12}$C+$^{12}$C threshold, which predominantly decay by $^{20}$Ne(g.s)+$\alpha$. These states were not observed in $^{20}$Ne($\alpha$,$\alpha_0$)$^{20}$Ne resonance scattering suggesting that they may have a dominant $^{12}$C+$^{12}$C cluster structure. Given the very low angular momentum associated with sub-barrier fusion, these states may play a decisive role in $^{12}$C+$^{12}$C fusion in analogy to the Hoyle state in helium burning [1]. We present estimates of updated $^{12}$C+$^{12}$C fusion reaction rates based on these newly observed potential resonances.

[1] P. Adsley. M. Heine, D.G. Jenkins et al., Phys. Rev. Lett. (in press)

Speaker: David Gareth Jenkins (University of York (GB))

EUNPC22 Jenkins.pdf

128 The role of deformation in the 17C structure and its influence in transfer and breakup reactions

Light exotic nuclei are so close to neutron or proton driplines that they are usually described within two- or three-body models made of an inert spherical core and one or two nucleons barely bound. However, deformation plays a key role in certain areas of the Segrè Chart, thus the need of going beyond a spherical picture for certain nuclei. This is the case of $^{17}$C.

Deformed two-body models are used to describe the structure of $^{17}$C. They consist of a neutron moving under the action of a deformed potential generated by the core. On the one hand, we have considered the semi-microscopic particle-plus-AMD (PAMD) model from [Phys. Rev. C 89 (2014) 014333], assuming weak-coupling between the fragments. On the other hand, we consider a model based on Nilsson assuming strong-coupling.

Energies and associated wave functions are obtained by diagonalizing the Hamiltonian in a transformed Harmonic Oscillator basis (THO). This basis has been successfully applied to the discretization of the continuum of two-body and three-body weakly bound nuclei for the analysis of break up and transfer reactions [Phys. Rev. Lett. 109 (2012) 232502, Phys. Rev. C 94 (2016) 054622].

The aforementioned structure models for $^{17}$C are tested by studying the transfer reaction $^{16}$C(d,p)$^{17}$C. Good agreement is found for the transfer to bound states by comparing with the experimental data from [Phys. Lett. B 811 (2020) 135939]. Preliminary results for the transfer to the unbound states of 17C have also been obtained. In addition, the continuum is studied performing a break up reaction, comparing with the experimental data from [Phys. Lett. B 660 (2008) 320].

Speaker: Pedro Punta (Universidad de Sevilla)

Slides.pdf

129 Study of light hypernuclei in Europe: the hypertriton and nn$\Lambda$ puzzles

The current understanding of the light hypernuclei, sub-atomic nuclei with strangeness, is challenged and studied in detail by several European research groups and collaborations [1, 2, 3, 4, 5].
In recent years, hypernuclear studies performed using high-energy heavy ion beams have reported unexpected results on the three-body hypernuclear state $_\Lambda^3$H, named the hypertriton. Its shorter lifetime [3, 6, 7, 8, 9, 5, 10] and larger binding energy [11] than the accepted understanding has created a puzzling situation for its theoretical description, the so-called "hypertriton puzzle". Additionally the possible neutral bound state of a $\Lambda$ hyperon with two neutrons, nn$\Lambda$ [12] has questioned our comprehension of the formation of light hypernuclei bound or resonance state. These results have initiated several ongoing experimental programs all over the world to study these three-body hypernuclear states precisely. We are studying those light hypernuclear states by employing heavy ion beams at 2$A$GeV on a fixed carbon target with the WASA detector system and the Fragment separator FRS at GSI [4]. The WASA-FRS experimental campaign was performed during the first quarter of 2022, and the data analyses are in progress.

Additionally, our collaboration between CSIC and RIKEN search and identify with machine learning techniques hypernuclei present in the nuclear emulsions irradiated by kaon beams in the J-PARC E07 experiment [13]. At the moment, we focus on measuring the hypertriton binding energy at the world's best precision [4]. We have already uniquely identified events associated with its decay, and the determination of the binding energy is underway.

A quick overview of the European efforts in the study of hypernuclei will be given before focusing on the experimental study of the light hypernuclei in the WASA-FRS HypHI experiment. The measurement of the lifetime of $_\Lambda^3$H and $_\Lambda^4$H is the first goal of the experiment. The possible observation of the nn$\Lambda$ state is the second part of the WASA-FRS research program. Details of the experiment and preliminary results will be discussed. The measurement of the hypertriton binding energy in the nuclear emulsion analysis will also be reported to exhibit the European participation in tackling the second aspect of the hypertriton puzzle. The future perspectives will then conclude this contribution.

References:

• [1] P. Eckert, et al. for the A1 collaboration, in
  Proceedings of 22nd Particles and Nuclei International Conference
  (PANIC 2021), 380, (2022)
• [2] S. Simon, for the HADES collaboration,  EPJ Web of Conferences, 259, 01007 (2022)
• [3] C. Rappold et al. for HypHI collaboration, Nucl. Phys. A 914, 519 (2013).
• [4] T. R. Saito, et al., Nature Reviews Physics 3, 803 (2021).
• [5] J. Adam, et al., for ALICE collaboration, Phys. Lett. B 754, 360 (2016).
• [6] The STAR Collaboration, Science 328, 58 (2010).
• [7] Y. Xu for the STAR Collaboration in Proceedings of the 12th International Conference on Hypernuclear and Strange Particle Physics (HYP2015) 021005 (2017).
• [8] L. Adamczyk, et al., Phys. Rev. C 97, 054909 (2018)
• [9] J. Chen, et al., Phys. Rep. 760, 1 (2018).
• [10] S. Acharya, et al., Phys. Lett. B 797, 134905 (2019)
• [11] J. Adam, et al., Nat. Phys. 16, 409 (2020).
• [12] C. Rappold, et al., Phys. Rev. C 88, 041001 (2013).
• [13] H. Ekawa, et al., Prog. Theor. Exp. Phys. 2019, 021D02
  (2019).

Speaker: Christophe Rappold (Instituto de Estructura de la Materia - CSIC)

EuNPC2022_WASAFRS-HypHI.pdf

16:45 Coffee Break

P2 Nuclear Structure, Spectroscopy, and Dynamics

130 Precision Studies at the Intersection of Nuclear Structure, Atomic and Astrophysics

Tremendous efforts are undertaken worldwide to produce secondary beams at radioactive ion beam facilities. Their incarcerating in a dedicated ring or a trap is a straightforward way to achieve the most efficient use of such rare species. In this context, employing heavy-ion storage rings for precision physics experiments with highly-charged ions (HCI) at the intersection of atomic, nuclear, plasma and astrophysics is a rapidly developing field of research. The present contribution will concentrate on recent highlight results obtained within the FAIR Phase-0 research program at storage ring facilities of GSI, Darmstadt. These are the experimental storage ring ESR and the recently commissioned dedicated low-energy storage ring CRYRING.
The focus will be laid at studies of exotic decay modes. The ESR is presently the only instrument enabling precision studies of decays of HCIs. First, the measurement of the bound-state beta decay of fully-ionized $^{205}$Tl was proposed about 35 years ago and was finally accomplished in 2020. Implementation of combined Isochronous and Schottky mass spectrometry enabled us to directly measure two-photon decay branch of the first 0+ state in $^{72}$Ge.
The performed experiments will be put in the context of the present research programs at GSI/FAIR and in a broader, worldwide context, where, thanks to fascinating results obtained at the presently operating storage rings, a number of new exciting projects is planned.

Speaker: Yuri Litvinov (GSI, Darmstadt)

131 Physics results with the ultimate AGATA-MUGAST-VAMOS setup and ISOL beams at GANIL

The AGATA-MUGAST-VAMOS set-up, which was recently available at GANIL, combined the state-of-the-art gamma-ray tracking array AGATA with the highly-segmented silicon array MUGAST and the large-acceptance magnetic spectrometer VAMOS. The mechanical and electronics integration provided a maximum efficiency for each device. The superb sensitivity of the complete set-up offered a unique opportunity to perform exclusive measurements of direct reactions with radioactive beams delivered by the SPIRAL1 facility.

An experimental campaign using radioactive ISOL beams was performed during 2019-2021 using the cutting-edge combined setup, covering physics cases ranging from oxygen-14 to argon-46, and topics from nuclear structure and dynamics to astrophysics.

In this contribution I'll review the performance of the setup an focus on the physics results of the experimental campaign.

Speaker: Daniele Mengoni (Universita e INFN, Padova (IT))

DMengoni_EuNPC22_FINAL.pdf

132 Nuclear isomerism in odd-Au isotopes

Decay studies are of high demand since they complement existing in-beam data and provide a valuable information about non-yrast states. These states are of particular interest since they carry an information on the nuclear deformation. Deformation parameters, both axial and triaxial can be deduced from the spectra of excited states of the odd-mass nuclei. The particle-core coupling models [1] suggest a very strong dependence of excitation energies of states with various spins. This allows to deduce the $\gamma$ deformation parameter from measured spectra of the odd-mass isotopes. The non-yrast states can be accessed via the internal transition decay of isomers with high excitation energy.
Such isomer was very recently discovered in $^{179}$Au [2]. The data were acquired at the RITU separator at JYFL. The decay path of the hitherto unknown isomer with 2.15$~\mu$s half-life has been investigated. The level scheme of the new isomer was constructed. Decays into known rotational bands [3] were observed. However, many more isomeric $\gamma$ rays were observed but could not be unambiguously assigned. Strong signature of $^{179}$Au is the internal transition decay of the 326$~$ns isomer with $I^{\pi}$ = 3/2$^-$ [4,5]. It emits low-energy $\gamma$ rays with energies of 27, 62 and 89 keV. Several isomeric $\gamma$ rays, observed in the data, are interpreted as decays of the isomeric state in $^{179}$Au, and are found to feed the known 3/2$^-$ isomer. One of the prominent $\gamma$ rays is observed with the different half-life, thus suggesting existence of other isomers in this nucleus. Calculations based on the PTRM model [6] were performed to interpret the data. The analysis paved the road for the dedicated experiment.
Studies of these isomers provide not only a unique chance to investigate the $K$ isomerism (or other types of isomerism) in odd-Au isotopes, but also to study non-yrast states in $^{179}$Au. Isomeric states act as “feeders” of these states. It seems that presently, this is the only chance how to investigate them. It becomes even more evident in the heavier odd-Au isotopes. Therefore, these isomers allow us to extend our understanding of the nuclear structure of odd-Au isotopes.

References
[1] J. Meyer-ter-Vehn, Phys. Rev. Lett. 32, 24 (1974).
[2] M. Balogh et al., submitted to Phys. Rev. C.
[3] W. F. Mueller et al., Phys. Rev. C 69, 064315 (2004).
[4] M. Venhart et al., Phys. Lett. B 695, 82 (2011).
[5] M. Venhart et al., Phys. Lett. B 806, 135488 (2020).
[6] S. E. Larsson, G. Leander, and I. Ragnarsson, Nucl. Phys. A 307, 189 (1978).

Speaker: Dr Andrej Herzáň (Institute of Physics, Slovak Academy of Sciences)

133 Spectroscopic investigation of low-lying T=0,1 states in self-conjugate $^{62}$Ga

The assignment of the first 2$^+$ state in $^{62}$Ga has been a subject of debate in the last decades due to its implications in triplet energy difference systematics in this mass region[1]. To clarify this, an experiment was performed at the IFIN-HH 9-MV Tandem accelerator using the ROSPHERE[2] array in a mixed configuration of LaBr$_3$(Ce), HPGe and liquid scintillator neutron detectors. Excited states in $^{62}$Ga were populated through the $^{58}$Ni($^{6}$Li, $2n $) fusion-evaporation reaction. The precise angular anisotropy ratio determined in this experiment for a 978.1-keV transition to the ground state in $^{62}$Ga reveals that we have indeed populated the lowest-lying 2$^+$ state. This state's newly assigned spin and parity positions the $A=62$ isovector triplet within the typical range of values in the $T=1$, $J^\pi = 2^+$ fractional triplet energy difference systematics. The interplay between the isospin-symmetry breaking and shape-coexistence effects in the $A=62$ isovector triplet was theoretically treated within the beyond-mean-field complex excited Vampir variational model. Theoretical results indicate agreement with the experimental data on the discussed observables.

[1] T.W. Henry $\it et$ $al.$, Phys. Rev. C 92, 024315 (2015).
[2] D. Bucurescu $\it et$ $al.$, NIM A 837 (2016).

Speaker: Radu-Emanuel Mihai (Horia Hulubei National Institute of Physics and Nuclear Engineering (RO))

Mihai 62Ga - santiago de compostela.pdf

134 Shell evolution in Sc isotopes

Shell evolution [1,2] is one of the most discussed topics in the last two-decades in nuclear structure physics. It reveals that the traditional shell structure known for stable nuclei changes when we go towards the neutron-drip line. Recently, the low-energy states of neutron-rich $^{55}$Sc has been populated in an experiment [3], in which the first excited state $(3/2)^-$ has been found near 0.5 MeV. Since the structure of $^{55}$Sc includes one proton above the closed Z = 20 core, the low-excitation energy of this state points to the disappearance of the traditionally large proton $1p_{3/2}$-$0f_{7/2}$ energy gap in the neutron-rich region. In order to into look this point in detail, we have performed theoretical calculations within the shell-model framework [4]. We have found out that the proton $1p_{3/2}$-$0f_{7/2}$ energy gap reduces at $^{55}$Sc but the $(3/2)^-$ state does not gain its excitation energy from this gap. In fact, this state mainly originates from the transition of a neutron across the N = 34 semi-magic shell gap. Thus, its low-excitation energy indicates the weakening of this gap above Ca.

References:
[1] T. Otsuka et al., Phys. Rev. Lett. 95, 232502 (2005).
[2] T. Otsuka et al., Rev. Mod. Phys. 92, 015002 (2020).
[3] D. Steppenbeck et al., Phys. Rev. C 96, 064310 (2017).
[4] P. Kumar et al., Phys. Rev. C 100, 024328 (2019).

Speaker: Dr Pawan Kumar (Technische Universität Darmstadt, Darmstadt and GSI Helmholtzzentrum für Schwerionenforschun, Darmstadt)

P4 Astroparticle Physics

135 Latest results from the CUORE experiment

The Cryogenic Underground Observatory for Rare Events (CUORE) is the first bolometric experiment searching for 0νββ decay that has been able to reach the one-tonne mass scale. The detector, located at the LNGS in Italy, consists of an array of 988 TeO2 crystals arranged in a compact cylindrical structure of 19 towers. CUORE began its first physics data run in 2017 at a base temperature of about 10 mK and in April 2021 released its 3rd result of the search for 0νββ, corresponding to a tonne-year of TeO2 exposure. This is the largest amount of data ever acquired with a solid state detector and the most sensitive measurement of 0νββ decay in 130Te ever conducted, with a median exclusion sensitivity of 2.8×10^25 yr. We find no evidence of 0νββ decay and set a lower bound of 2.2 ×10^25 yr at a 90% credibility interval on the 130Te half-life for this process. In this talk, we present the current status of CUORE search for 0νββ with the updated statistics of one tonne-yr. We finally give an update of the CUORE background model and the measurement of the 130Te 2νββ decay half-life, study performed using an exposure of 300.7 kg⋅yr.

Speaker: Emanuela Celi

EuNPC2022_celi.pdf

136 The NEXT experiment at the Canfranc Underground Laboratory (a neutrino-less beta decay search in 136Xe))

NEXT (Neutrino Experiment with a Xenon TPC) is an international collaboration with the objective of searching for neutrinoless double beta decay in xenon. After an initial R&D phase in which the TPC technology was developed, it was able to successfully run a small (5 kg of xenon) detector, NEXT-White (2016-2021). The detector was hosted at Laboratorio Subterráneo de Canfranc, an underground facility in the Spanish Pyrenees in the border between Spain and France. During this period it demonstrated the essential features of a neutrinoless double beta experiment, to be discussed in this talk: excellent energy resolution, active background discrimination through the combination of both energy and tracking capabilities, and a reliable measurement of the double beta two neutrino mode half-life of Xe-136.

The current phase consists of the construction (ongoing) and operation of a larger (100 kg of xenon) detector, NEXT-100. The data taking is expected to start during the last quarter of 2022. Being a low background experiment, detector materials must be carefully selected and measured. In addition, a reliable simulation of the detector and physics processes is needed in order to evaluate the background contribution to the signal region. This talk also discusses the simulation of the background model for NEXT-100 and its projected physics reach.

Speaker: Mr Gonzalo Díaz Lopez (Universidade de Santiago de Compostela)

eunpc_2022_final.pdf

137 BINGO: Bi-Isotope 0ν2β Next Generation Observatory

Neutrinoless double-beta decay (0νββ) is a hypothetical rare nuclear transition. Its observation would provide an important insight about the nature of neutrinos (Dirac or Majorana particle) demonstrating that the lepton number is not conserved. BINGO aims to set the technological and conceptual grounds for future bolometric 0νββ experiments. It is based on a dual heat-light readout, i.e. a main absorber embedding the double-beta decay isotope faced by a light detector. Dual heat-light readout helps to reject the α background component, thanks to the lower light output of α’s compared to β/γ’s. BINGO will study two of the most promising isotopes: 100Mo embedded in Li$_2$MoO$_4$ and $^{130}$Te embedded in TeO$_2$. BINGO’s proposed technology aims at reducing dramatically the background in the region of interest, thus boosting the discovery sensitivity of 0νββ. This can be achieved by fulfilling the following goals: (i) increasing the light detector sensitivity thanks to Neganov-Luke amplification; (ii) having a revolutionary detector assembly that will reduce the total surface radioactivity contribution; (iii) using an active shield, based on ZnWO$_4$ or BGO scintillator with bolometric readout, to suppress the external gamma background. The proposed solutions will have a high impact on next-generation bolometric tonne-scale experiments, like CUPID.
In this talk i will present the first results on the bolometric veto and the new detector assembly.

Speaker: Hawraa Khalife (IRFU/CEA (France))

BINGO_EUNPC2022_khalife_final.pdf

P5 Heavy Ion Collisions and QCD Phases

138 ALICE measurement of $\psi(2\rm{S})$ production in Pb--Pb

Charmonia, bound states of charm quark-antiquark pairs, represent an important tool to study creation and evolution of a medium produced in collisions of ultra-relativistic heavy ions, the quark-gluon plasma (QGP).
Production of the charm quark-antiquark pair takes place in the early stages of the collision while the subsequent hadronization into a bound state happens on a much larger time scale. In the presence of QGP, the high number of color charges in the deconfined medium screens the pair, leading to suppression of charmonium production. Concurrently, the abundance of charm pairs in the medium created at the LHC allows for a recombination of pairs and thus regeneration of charmonia within the QGP or at the transition between QGP and hadronic phase.

The $\psi(2\rm{S})$ meson is an excited charmonium state. Its much smaller production cross section compared to its ground-state counterpart, J/$\psi$ meson, renders measurement of $\psi(2\rm{S})$ much more difficult than that of J/$\psi$. Nevertheless, measurements of different quarkonium states in nuclear collisions are vital to better understand in which way their production is affected by the nuclear medium and to help distinguish between different regeneration scenarios.

This talk reviews recent ALICE results of $\psi(2\rm{S})$ production in Pb–Pb collisions at the LHC down to zero transverse momentum and at forward rapidity, most accurate to date.
The results will be discussed in context of other available charmonium data from the LHC and compared with theoretical models.

Speaker: Jana Crkovska (Ruprecht Karls Universitaet Heidelberg (DE))

Psi2SinPbPb_Crkovska_20221027.pdf

139 ALICE upgrades for Run 4

The ALICE collaboration pursues several upgrades to further extend the reach of heavy-ion physics at the LHC. For LHC Run 4 (2029-2032), ALICE is pioneering the use of bent, wafer-scale pixel sensors to produce truly cylindrical tracking layers with very low material budget to replace the three innermost layers of the inner tracking system. The resulting improvement in pointing resolution will allow new measurements of heavy-flavour hadrons and dielectrons. In addition, a Forward Calorimeter (FoCal) system combines a high-granularity electromagnetic silicon-tungsten calorimeter with excellent two-shower separation for neutral pion reconstruction with a conventional hadronic calorimeter for photon isolation. Direct photon measurements with FoCal will provide unique constraints on the low-x gluon structure of protons and nuclei via forward measurements of direct photons.
For Run 5 and beyond, a next-generation detector system, ALICE 3, has been conceived to gain unique access to the interaction and thermalisation of heavy flavour probes in the QGP as well as to the thermal radiation carrying information about the temperature and the restoration of chiral symmetry. At its core, it combines a high-resolution vertex detector with a large-acceptance silicon pixel tracker. For the identification of particles, a combination of a time-of-flight system, a Ring-Imaging Cherenkov detector, an electromagnetic calorimeter, a muon identifier, and a dedicated forward detector for ultra-soft photons, are envisaged.

Speaker: Prof. Stefania Maria Beole (Universita e INFN Torino (IT))

EuNPC_ALICE_Upgrades_beole_v5.pdf

140 Charm and beauty production measurements to constrain transport models with ALICE

Heavy quarks are effective probes to investigate the quark--gluon plasma (QGP) produced in heavy-ion collisions since they are primarily produced in hard-scattering processes before the formation of the QGP.
Therefore, measurements of heavy-flavour hadron production in nucleus--nucleus collisions are crucial to investigate the mechanisms of interaction of heavy quarks inside the QGP and test the predictions of in-medium energy loss calculations. In addition, they provide unique experimental capabilities to study the properties of heavy-quark hadronization in hadronic collisions.

In this contribution, we present the nuclear modification factors ($R_\mathrm{AA}$) of charm mesons and baryons, non-prompt strange and non-strange D mesons and heavy-flavour hadron decaying to leptons measured in Pb-Pb collisions at $\sqrt{s_\mathrm{NN}}=5.02$~TeV by the ALICE Collaboration.

In addition, the measurement of the azimuthal anisotropy of prompt and non-prompt D mesons is discussed. The second harmonic coefficient helps to investigate the degree of thermalization of charm and beauty quark in the hot and dense QCD medium. A systematic comparison of experimental measurements with model calculations will be presented to disentangle different model contributions and provide significant constraints to the QGP's charm-quark diffusion coefficient $D_s$.

Speaker: Stefano Politano (Politecnico di Torino (IT))

EuPNC_ALICE_SPolitano_27102022.pdf

P6 Hadron Structure, Spectroscopy, and Dynamics

141 J/ψ Near-Threshold Photoproduction off the Proton and Neutron with CLAS12

J/ψ near threshold photoproduction plays a key role in the physics program at the Thomas Jefferson National Accelerator Facility (JLab) 12 GeV upgrade due to the wealth of information it has to offer. J/ψ photoproduction proceeds through the exchange of gluons in the t-channel and is expected to provide unique insight about the nucleon gluonic form factor and the nucleon mass radius.

The JLab based CLAS Collaboration, which uses the CEBAF Large Acceptance Spectrometer (CLAS12), aims to measure the J/ψ near threshold photoproduction cross section using both a proton and a deuteron target. The latter further offers the possibility of comparing the proton and neutron gluonic form factors and mass radii in a first measurement of the ratio of the cross sections off a proton or neutron within the deuteron target. The analysis towards these measurements is ongoing and well advanced, with machine learning based techniques for particle and reaction identification already designed and tested on CLAS12 data taken towards these measurements.

This talk will describe the aims and experimental design for the measurement of J/ψ near threshold photoproduction off the proton and neutron with the CLAS12 detector along with the current stage of the data analysis.

Speaker: Mr Richard Tyson (University of Glasgow)

142 Kaonic atoms with SIDDHARTA-2 at the DAFNE collider

The study of the quantum chromodynamics (QCD) is the main motivation for the exotic hadronic atom experiments. Among the exotic atom, the kaonic atom spectroscopy plays a key role for the understanding of the low-energy QCD in the strangeness sector, by allowing to directly access the antikaon-nucleus ($\bar{\text{K}}$N) interaction at threshold. Currently, the lack of experimental inputs prevents the improvement and development of theoretical models, in particular the measurement of kaonic deuterium is the missing element to extract the isospin dependent $\bar{\text{K}}$N scattering lengths.
In this framework, the SIDDHARTA-2 experiment at INFN-LNF DA$\Phi$NE collider is carrying on its data taking campaign, aiming at performing the first measurement of kaonic deuterium X-ray transition to the fundamental level. To achieve this challenging goal the experimental apparatus is equipped with 384 state-of-the-art Silicon Drift Detectors (SDDs), distributed around its cryogenic gaseous target, and several trigger and veto systems for background reduction.
The scientific case, the SIDDHARTA-2 experimental apparatus as well as the results obtained during the first phase of the experiment will be presented.

Speaker: Francesco Sgaramella (INFN - National Institute for Nuclear Physics)

EuNPC22_Sgaramella.pdf

143 Kaonic atoms beyond SIDDHARTA-2: future measurements and perspectives at the DAFNE collider

The recent progress in the field of X-ray detection and their readout electronics contributed, in these last years, to a renewed interest in new and more precise measurements of kaonic atoms.
The DAFNE machine at the INFN Laboratories of Frascati is still the best facility in the world, in terms of purity of the kaon beam, luminosity, and kinematic conditions, where these important measurements can be carried on.
Beyond the SIDDHARTA-2 experiment, presently installed on the DAFNE Interaction Point exploiting 450 mm thick Silicon Drift Detectors (SDD) to measure for the first time X-rays from kaonic transitions in deuterium, several other important measurements are planned or proposed.
These new measurements, among which transitions in kaonic helium, carbon, sulfur, lead, wolfram, nitrogen, and molybdenum, are now feasible thanks to new technologies: 1 mm thick SDDs, CdZnTe, and HPGe detectors as well as crystal spectrometers and TES microcalorimeters.
In this talk, an overview of the already planned and foreseen measurements, together with others proposed for future campaigns, will be presented; for each one, the physics case, possible impacts, and details of the experimental setup will be given.

Speaker: Luca De Paolis

EuNPC2022 Luca De Paolis.pdf

EuNPC2022 Luca De Paolis.pptx

P8 Nuclear Physics Applications

144 Time-of-flight methods in ion beam analysis

Ion beams with MeV energies offer great possibilities for the characterization and investigation of different types of materials, from inorganic thin films to tissue sections. Using different primary ions and detectors, elemental or molecular composition, thickness, and depth profiles can be determined.
Most of the ion beam techniques are based on the interaction of light ions, such as protons or alphas, with the material. However, some information can be deduced only by analyzing secondary particles or molecules, in which case heavy incident ions have to be used. Two methods that utilize heavy ion beams in the MeV energy range for the production of secondary particles are Time-of-flight Elastic Recoil Detection Analysis (TOF-ERDA) and Time-of-flight Secondary Ion Mass Spectrometry (MeV TOF-SIMS). For both techniques, the time-of-flight of secondary particles or molecular ions is measured to determine their mass.
At the Ruđer Bošković Institute accelerator facility, both TOF-ERDA and MeV TOF-SIMS setups are built at the 0-degree beam line allowing the use of high-energy heavy ions. Using TOF-ERDA setup depth profiles of different elements/isotopes within thin films, including hydrogen and its isotopes, are routinely measured with 1 nm depth resolution and high detection efficiency. In the last few years, MeV TOF-SIMS setup with collimated beam and reflectron TOF analyzer was developed in the extension of TOF-ERDA setup for the analysis of organic samples (imaging of animal tissue sections, fingermarks, paintings, etc.).
In this talk, setups and examples of materials analysis will be presented, as well as challenges associated with the practical implementation, especially with the TOF measurement on the MeV TOF-SIMS setup.

Speaker: Dr Marko Brajković (Ruđer Bošković Institute)

Brajkovic Marko presentation.pdf

Brajkovic Marko presentation.pptx

145 Analysis of semiconductor detectors using MeV ion beams

In this talk, we will first briefly present the infrastructure available at the Centro Nacional de Aceleradores, based on a 3 MV tandem accelerator and a compact cyclotron, which are employed for different Nuclear Physics applications, as the characterization and modification of materials using Ion Beams, the development of nuclear instrumentation, the irradiation of electronic devices and the research with neutrons. Then we will describe the fundamentals of the Ion Beam Induced Current (IBIC) technique, a methodology employed to evaluate the spectrometric and transport properties of semiconductor detectors.
Some illustrative examples of the IBIC technique will be shown, including the dose rate dependence on the generation of point defects in Si diodes, the analysis of silicon-based Low Gain Avalanche Detectors (LGAD) for high energy physics research and the spectroscopic response of SiC diodes at high temperature with interest in nuclear fusion.

Speaker: Prof. Javier Garcia-Lopez (Centro Nacional de Aceleradores, Sevilla, Spain)

P9 Few-Body Systems

146 Scattering of 15C on 208Pb at energies near the Coulomb barrier

Nuclear systems such as 6He, 11Li, 11Be, 14Be are known to have extended neutron distributions: the so-called neutron halos [1, 2]. This feature occurs when the separation energy of valence neutrons is much smaller than the average binding energy per nucleon in a nucleus, so they can tunnel out of the nuclear potential to large distances with sizable probability. It has been an intense experimental and theoretical activity dedicated to study the existence of halos and their dynamics in reaction processes. The neutron halo produces a pronounced maxima at low excitation energies in the Coulomb dipole strength B(E1), very narrow transverse momentum distributions and large interaction cross-sections when measured at high energies [3].
The dynamics of the halo nuclei scattering at low energies, around the Coulomb barrier, is dominated by the coupling between the elastic channel and collective excitations, neutron transfer and breakup. The angular distributions of the elastic cross section and the core fragments present large sensitivity to these coupling effects, which are due to the halo configuration. This has been demonstrated by us in previous studies with light exotic beams of 6He, 11Li and 11Be scattered on heavy targets [4, 5, 6]. The angular distribution of the elastic channels shows strong absorption patterns where the nuclear and Coulomb interference completely disappears. The 15C nucleus (T1/2 =2.449(5) s) has a low single- neutron separation energy Sn=1218.1(8) keV in comparison with the two-neutron separation energy S2n=9394.5(8) keV [7]. The spins and parities of the ground and first excited state at E=740 keV are known to be Iπ=1/2+, 5/2+, respectively.
The halo structure of 15C has been investigated at relatively high energies in several experiments. The reaction cross section at high energy (83 MeV/u) shows an enhancement respect to the neighboring 14,16C isotopes and the longitudinal momenta of the 14C fragments after 1n-breakup present a FWHM distribution between 64-70 MeV/c depending of the target [8, 9, 10] that it is narrower than that of the neighbour 14,16C isotopes, ≈ 200 MeV/c, but wider than the ≈ 40-50 MeV/c found for the archetype cases [3]. These properties have hinted the presence of a halo configuration in the 15C nucleus that would be unique in the sense that it can be described with an almost pure s1/2 ground state wavefunction.
To complete our understanding of the role of the halo in 15C, we have studied its dynamical response at energies close to the Coulomb barrier that has not been yet probed until this work. We studied the scattering of 4.37 MeV/u 15C beam on a lead target at HIE-ISOLDE, CERN using the GLORIA setup [10]. We’ve also measured a stable beam of 12C under the same conditions. In this contribution, we will present the angular distribution of the elastic cross section of 15C + 208Pb relative to 12C in order to avoid solid angle uncertainties. Optical Model calculations properly describe the angular distribution of the elastic channel and indicate an enhancement of the total reaction cross section.

References
[1] I. Tanihata et al., Phys. Rev. Lett. 55, 24 2676 (1985).
[2] K. Riisager, Phys. Scr. T152, 014001 (2013).
[3] T. Aumann, Eur. Phys. J. A 26, 441 (2005).
[4] A.M. S ́anchez-Ben ́ıtez et al., Nuclear Physics A 803, 30 (2008). [5] M. Cubero et al., Phys. Rev. Lett. 109, 262701 (2012).
[6] V. Pesudo et al., Phys. Rev. Lett. 118, 152502 (2017). [7] M. Wang et al., Chin. Phys. C 36, 1603 (2012).
[8] D. Bazin et al., Phys. Rev. C 57, 2156 (1998).
[9] E. Sauvan et al., Phys Lett B 491, 1 (2000).
[10] D.Q. Fang et al., Phys. Rev. C 69 034613 (2004).
[11] G. Marqu ́ınez-Dur ́an et al., Nuc. Inst. and Methods in Phys. Res. A 755 69 (2014).

Speaker: Vicente Garcia Tavora (Consejo Superior de Investigaciones Cientificas (CSIC) (ES))

VGT_EUNPC_2022.pptx

147 R-Matrix study of the beta decay of 8B to the highly excited states of 8Be

The β$^+$/Ec-decay of the proton halo nucleus $^8B$ into $^8 Be$ is interesting for astrophysics and nuclear structure. From the astrophysical point of view, β-decay is the main source of high-energy solar neutrinos above 2 MeV and thus, the main contributor to what was known as the “solar neutrino problem” [1]. On the nuclear structure side, this decay can be used to probe the structure of $^8 B$ and populate the excited states of $^8 Be$. We are interested in learning about the nature of the 16.6 and 16.9 MeV excited states of $^8 Be$, previously only resolved in reaction experiments [2]. The totally isospin mixed character of the doublet has never been determined experimentally. The β$^+$/EC feeding to the doublet gives an opportunity to test this hypothesis, until the present work the individual feeding to the doublet could not be resolved.

Within the Q-value window, the following states in $^8Be$ are available: the broad $2^+$ state at 3 MeV [3], which is the dominant state and the primary source of high-energy solar neutrinos. A $2^+$ isospin doublet consists of two narrow levels at 16.6 and 16.9 MeV, with dominant configurations of $^7Li$+p and $^7Be$+n respectively. This doublet is the only case known of almost equal isospin mixing between nuclear states [2]. The decay through the doublet will have a Fermi part that will only go to the T=1 component, and a Gamow-Teller strength only to T= 0.

There is also a highly excited $1^+$ level at 17,640 MeV that decays by low energy (330 keV) proton emission into $^7Li$. The EC-feeding to this state has not yet been observed. Assuming that the wave function of a halo nucleus can be factorised [4] into a core and a halo (in this case, a proton), one could model the $β^+$/EC-decay as occurring in the core with the halo proton as a spectator. The strength of this branch has been estimated from the decay of the $^7Be$ nucleus resulting in a value of the order of $10^{-8}$, see [5] for details.

The β$^+$/EC of 8B to $2^+$ states in $^8Be$ break up into two α particles, due to the broad nature of the 3 MeV $2^+$ state, it results in an α-continuum spectrum. The decay of 8B into the 16.626(3) MeV state has been observed by several groups, but the (mainly EC) decay into the 16.922(3) MeV state was first hinted at the previous JYFL08 experiment [6], where 5 events were attributed to the breakup of this state.

To study the nature of the doublet and other highly excited states in $^8$Be, the IS633 was performed at the ISOLDE facility at CERN. The experimental setup consisted of 4 particle-telescopes formed by a Double-Sided Silicon strip Detector (DSSD) of 40-60 $\mu$m thickness and stacked with a 1000 $\mu$m thick Si-PAD detector. Additionally, a thick 500 $\mu$m DSSD was placed below the implantation foil to maximize the angular coverage. At the centre of the setup, a carbon foil catcher of 30 $\mu$m/cm2 was placed to stop a 50 keV $^8B$ beam, more details in [7]. The high statistics of our experiment allowed us to resolve the feeding to the doublet for the first time in a $^8$B beta decay study.

The alpha-alpha coincidence spectrum was unfolded with the response function of the detector setup and the convoluted spectrum was analysed using the R-Matrix formalism to extract the feeding to the 2$^+$ states in $^8$Be. In this formalism, the spectrum can be decomposed into the contributions of individual resonant levels. R-Matrix offers a way of analysing complex data that cannot be fitted with simple analytic functions (Gauss, Landau, etc). The spectrum is factorized in terms of a series of nuclear resonances, each characterized by a series of parameters (energy, decay width, and beta feeding), the values of these parameters are incrementally modified until the R-matrix calculation fits the experimental data, the fitted parameters will give us the physical observables of our system.

In this contribution, we discuss the current results and comment on possible additional analysis of this data. We have tested the consistency of the results through a series of cross-checks, in each test the R-matrix fits were repeated with a series of constraints applied to the data, in addition, we also compared the obtained results to previous experimental results [6]. We will present the observables deduced, the limitations of the R-Matrix fit and the isospin mixing found for the doublet.

References
[1] J. N. Bahcall and C. Peña-Garay, New Journal of Physics 6 (2004) 63.
[2] D.R. Tilley et al., Nuclear Physics A 745 (2004) 155 -362.
[3] F. C. Barker, Australian Journal of Physics 22 (1969) 293–316.
[4] T. Nilsson et al., Hyperfine Int. 129, 67 (2000).
[5] M.J.G. Borge et al., J. Phys. G 40, 035109 (2013).
[6] O. Kirsebom et al. Phys. Rev. C 83 (2011) 1–21.
[7] S.Viñals, PhD thesis 2020. Complutense University of Madrid, (https://cds.cern.ch/record/2748191).

Speaker: Daniel Fernandez Ruiz (Consejo Superior de Investigaciones Cientificas (CSIC) (ES))

Daniel Fernandez Ruiz-EuNPC-Presentacion-V10.pdf

Daniel Fernandez Ruiz-EuNPC-Presentacion-V10.pptx

148 Low-lying structure of 15C : information on the N=8 shell gap

The low-lying structure of $^{15}$C has been investigated via the neutron-removal d($^{16}$C, t) reaction. The experiment was performed at GANIL using a secondary $^{16}$C beam produced by fragmentation in the LISE spectrometer at 17.2 MeV/nucleon with an intensity of 5 × 10$^{4}$ pps and 100\% purity. The angle and energy of the light ejectile were detected by three MUST2 telescopes [1,2]. The missing mass technique was used to reconstruct the excitation energy of $^{15}$C. In this spectrum, two states were observed below the neutron separation threshold, and in the unbound region two resonances were located. From the differential cross sections information on the angular momentum of the transferred nucleon and spectroscopic factors were deduced.

The excitation energies and the deduced spectroscopic factors of the negative parity states placed above the neutron separation energy are an important measure of the 2p-3h configurations in $^{15}$C. Our results reveal an increasing shell gap at N=8 as protons are added to the 1p$_{1/2}$ orbital. This effect is well reproduced by state of the art shell model calculations such as SFO-tls [3].

References

[1] Y. Blumenfeld et al., Nucl. Instrum. Methods A 421 (1999) 471.
[2] E. Pollacco et al., Eur. Phys. J. A 25 (2005) 287.
[3] T. Suzuki, R. Fujimoto and T. Otsuka, Phys. Rev. C 67 (2003) 044302

Speaker: Juan Lois

EUNPC-V4.pdf

149 Study of 20Ne spectroscopy from new experiments on 19F(p,a0) and A New Phenomenological Model for the description of Heavy-Ion Fusion Cross Sections

In this contribution we will discuss new results obtained by performing high precision experiments of proton induced transmutation of fluorine in direct kinematics, with the aim of studying both the α_0 and α_π reaction channels, leading respectively to the 16O residual nucleus in the ground and the first excited states. This reaction has been subject of a large interest in recent times, both as a tool to investigate the occurrence of clustering of the 20Ne compound nucleus here formed, and for its involvement in exotic nuclear astrophysics context linked to studies of CNOF breakout reactions.

The experiment was performed at the Singletron electrostatic accelerator in Catania (Italy) by colliding a proton beam of energies Ep=1.15-1.34 MeV and Ep=1.64-1.74 MeV onto a calcium fluoride layer deposited on a thin carbon backing. The detection system was made by an high resolution solid state detector, placed onto a movable arm allowing a very accurate geometrical positioning. The bombarding energy region here investigated would allow (1) to solve conflicting estimates previously reported in the literature for the α_0 channel and (2) to investigate for the first time the astrophysical factor of the α_π channel in a region where no data are reported in the literature. The excellent angular and energy resolutions allowed us to perform an internal normalization procedure to estimate the absolute cross sections, based on the analysis of the elastic scattering signals. We will therefore discuss the preliminary results obtained from this investigation, with a particular emphasis on the impact of such new data on the structure of 20Ne in the 13 MeV excitation energy region.

Speaker: Ivano Lombardo (INFN Sezione di Catania)

EuNPC22_Lombardo.PPTX

Conference Dinner

Friday 28 October

Plenary Talks

150 NUCLEAR PHYSICS CAPABILIESTIES OF THE IFMIF-DONES NEUTRON SOURCE

The International Fusion Materials Irradiation Facility – Demo Oriented Neutron Source (IFMIF-DONES) is a research infrastructure for irradiation the materials to be used in a fusion reactor. The facility would provide a unique neutron source of energy spectrum and flux level representative of those expected for the first wall containing future fusion reactors. Its construction is close to be started in the proposed site at the Escúzar Metropolitan Park (located 18 km southwest from Granada city).
Its unique characteristics are also well adapted for the development of a number of different types of other experiments relevant for nuclear physics and other scientific topics.
This paper will present an overview of the implementation, engineering design and main irradiation characteristics of the facility as well as a review of the different possible experimental applications of interest for nuclear physics that has been identified.

Speaker: Angel Ibarra (IFMIF-DONES España)

221028DONES-v1.pdf

221028DONES-v1.pptx

151 Applications of high energy focused ion beams for elemental and molecular imaging in live sciences: micro-PIXE and MeV-SIMS

By the improvements of the accelerators, ion sources, ion lenses and detectors, high energy focused ion beams are becoming a powerful tool for chemical imaging in life science.

Micro-Proton-Induced X-ray Emission (micro-PIXE) became a technique of choice for tissue elemental mapping in the cases, where high elemental sensitivity, high lateral resolution and quantitative nature of the elemental analysis need to be combined for the tissue analysis. Quantification of the elemental maps is done with supplementary information obtained by Elastic Backscattering Spectrometry (EBS) and Scanning Transmission Ion Microscopy (STIM), providing light element composition and tissue thickness. We will present several representing cases of elemental imaging of biological tissue slices [1], including the samples in frozen hydrated state. We will present the capability for a single cell imaging, where elemental inventories of single cells are determined by picogram (10-12 g) resolution [2].

Combining lateral resolution, high elemental sensitivity and inherent concentration quantification capabilities, micro-PIXE is able to determine the stoichiometry of proteins containing metal atoms by ratio between the number of metallic atoms and sulphur atoms in proteins. The pioneering work was done by Garman and Grime [3] on natural proteins. In the work of Malay et al [4], we applied micro-PIXE to determine the number of gold atoms binding together TRAP protein rings into a synthetic protein cage structure featuring reversible self-organization.

Heavy ions with the energies of several MeV (swift ions) interact with the insulating media exclusively through interaction with the target electrons and create a phonon shock wave, which propagates from the ion impact position through the surrounding material and induces highly efficient desorption of entire ionized biomolecules. Based on this physical phenomenon, a Secondary Ion Mass Spectrometry with high-energy heavy ions (MeV-SIMS) is emerging as a promising Imaging Mass Spectroscopy (IMS) technique for molecular imaging of biological tissue [5]. Selected cases of molecular imaging by MeV-SIMS will be presented [6].

References:

[1] Pongrac et al, Food Chem. Toxicol. 135, 110974 (2020).
[2] Ogrinc et al, Nucl. Inst. Meth. B 306, 121-124 (2013).
[3] Garman and Grime, Progr. Biphys. Mol. Biol. 89, 173-205 (2005).
[4] Malay et al, Nature 569, 439–443 (2019).
[5] Nakata et al, Appl. Surf. Sci. 255, 1591-1594 (2008).
[6] Jeromel et al, Plos One 17, e0263338(2022).

Speaker: Primož Pelicon (Jožef Stefan Institute)

152 Applications of accelerator mass spectrometry radiocarbon dating in forensics

Different studies have shown the high potential of AMS (Accelerator Mass Spectrometry) 14C dating in forensics sciences where high chronological resolution (annual or even sub annual) is mandatory on samples typically younger than one hundred years ca. In this field, radiocarbon dating is based on the detection of the excess of the atmospheric radiocarbon concentration induced by aboveground nuclear detonation tests carried out after the second world war. The curve (bomb peak) representing the variation of the 14C atmospheric concentration is well known with high resolution for several locations around the globe both in the Northern and the Southern hemispheres and it is widely used as reference for forensics dating. Indeed, though different studies have shown the potential of the method in different fields (such as in forensics anthropology), important aspects have to be considered and addressed when the method is used in the routine forensics practice. These aspects such as the possible multiple intercepts with the bomb spike curve, possible regional offsets, considerations related to carbon fixation and turnover in living tissues are presented and discussed refereeing to different kind of materials. The achievable uncertainty levels are also discussed as well as the advantages related to the use of advanced statistical tools for data interpretation.
We also report on the outcome of a Work Package (WP4) specifically dedicated to 14C within a CRP-Coordinated Research Program funded by the International Atomic Energy Agency and aimed at enhancing the use of nuclear based techniques in forensics. Within the CRP different intercomparison exercises were designed and run among different AMS laboratories on sample materials relevant in forensics such as bones, ivory, foodstuff, paper, and textiles.
Case studies will be also presented and discussed such as the dating of seized ivory samples, the analysis of human remains, the identification of forgeries in cultural heritage and the identification of missing persons in war scenarios.

Speaker: Prof. Gianluca Quarta (University of Salento)

Talk_quarta_EUNPC_2022.pdf

Talk_quarta_EUNPC_2022.pptx

10:45 Coffee Break

Plenary Talks

153 From correlations to universal behavior in few-nucleon systems

Very detailed nucleon-nucleon (NN) and three-nucleon (3N) interactions have been constructed and applied to describe bound and scattering states in few-nucleon systems. They are based on chiral perturbation theory. At the same time the shallow character of the deuteron (S=1) state and the virtual 1S0 states allows for an effective description in which the pion degrees of freedom have been integrated out. This is known as pionless effective field theory. Different types of correlations appear; examples will be shown in the three- and four-nucleon systems and in the evolution of the nuclear levels from the unitary point, a point where the scattering lengths are infinity, to the physical point in which they take the observed value.

Speaker: Alejandro Kievsky (INFN)

kievsky_ENP.pdf

NPD Best PhD

154 High-precision measurements in the direct vicinity of the doubly magic 100Sn (N=Z=50) at ISOLDE/CERN

This dissertation award talk will describe the transition of the ISOLTRAP mass spectrometer at CERN from the well-established Penning-trap mass spectrometry (PTMS) technique, ToF-ICR, to the next-generation PTMS technique, called PI-ICR [PRL 110 (2013) 082501]. Using this revolutionary technique, we achieved the first mass measurements of the neutron-deficient indium isotopes $^{99-101}$In in the direct vicinity of the doubly-magic $^{100}$Sn ($N$=$Z$=50). These results allowed us to resolve a stark discrepancy in the β-decay energy of $^{100}$Sn and thus provided a new atomic mass value of $^{100}$Sn via its direct β-decay into $^{100}$In [Nature Phys. 17, 1099 (2021)].

In this context, I will also present the first hyperfine spectroscopy results of these neutron-deficient indium isotopes, which provided the first experimental evidence for the nuclear deformation toward the doubly-magic $^{100}$Sn.

Speaker: Jonas Karthein (Massachusetts Inst. of Technology (US))

2210.EuNPC-DissertationAward-talk-JonasKarthein.pdf

155 Laser spectroscopy at the frontiers of RIB production

The nuclear electromagnetic moments and changes in the charge radius are sensitive tools to investigate phenomena emerging in short-lived isotopes. These properties, extracted from laser spectroscopy experiments, are often essential to critically examine our understanding of the nuclear structure, and its evolution towards the edges of the nuclear landscape. In this contribution, recent highlights will be presented from the Collinear Resonance Ionization Spectroscopy (CRIS) experiment at ISOLDE and the collinear laser spectroscopy setup at the IGISOL facility, focusing on exploring the sensitivity of the charge radii to changes in the nuclear structure.

New technical developments enabled the CRIS measurement of the neutron-rich $^{52}$K and demonstrated the feasibility of spectroscopy on the isotope $^{34}$Al as well. These results contribute to tackling the questions associated with the proposed magic number at $N$=32 in the calcium region and the island of inversion near $N$=20, respectively. Furthermore, at IGISOL the proton-rich isotopes below Ni ($Z$=28) were explored by performing the first laser spectroscopy of radioactive $^{48,49,51}$Cr and $^{54-55,58}$Co. These results pave the way for measuring the properties of the isospin partners in self-conjugate $^{54}$Co, and $^{53}$Co together with its proton emitter isomer.

Speaker: Agota Koszorus (CERN)

AK_EuNPC 2022.pdf

156 Observing the shape of nuclei at high-energy colliders

High-energy nuclear collisions are conducted in the world’s largest accelerator facilities to characterize the hot and dense phase of strong-interaction matter, the quark-gluon plasma (QGP). Production of QGP droplets began with 197Au+197 collisions at the BNL RHIC in the early 2000's, and was followed in 2010 by 208Pb+208Pb collisions at the CERN LHC.

Thanks to data recently collected in collisions of additional systems, namely, 238U, 129Xe, 96Ru, 96Zr, it has been realized that the final states of heavy-ion collisions are strongly impacted by the collective structure (deformations and radial profiles) of the colliding ions. Nuclear structure manifests, in particular, in the azimuthal momentum anisotropy of the observed particle distributions, which, by virtue of the fluid-like nature of the QGP, directly reflects the deformed shape of the colliding ions at the time of interaction.

I present recent activities that have established high-energy nuclear experiments as a new probe of nuclear structure. I discuss signatures of quadrupole, octupole, and triaxial deformations of nuclei in heavy-ion collisions. I argue that these experiments provide an information about nuclear structure that is fully complementary to that obtained in traditional low-energy experiments, while opening a unique window onto the role played by QCD, i.e., by quarks and gluons, in shaping the collective properties of atomic nuclei.

Speaker: Giuliano Giacalone (Universität Heidelberg)

Giacalone_talk#2.pdf

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