The experiments at HIE-ISOLDE [1] made use of all three beam lines in 2018. Higher than before maximum energies of the post-accelerated radioactive ion beams were achieved with the installation of the fourth cryomodule of the linac now pushing towards the design value of 10 MeV/u. Majority of the experiments utilised the first beam line with the MINIBALL HPGe-detector array [2] for...
The 28Mg(d,p)29Mg reaction has been carried out using a 9.47 MeV/u radioactive ion beam from HIE-ISOLDE. This is the first physics measurement using the newly commissioned ISOLDE Solenoidal Spectrometer (ISS), which was used to detect the outgoing ions from the reaction. ISS is a spectrometer optimized for the study of direct reactions in inverse kinematics and is conceptually similar to the...
We have carried out measurements, using Miniball, of the $\gamma$-ray de-excitation of $^{222,228}$Ra and $^{222,224,226}$Rn nuclei Coulomb-excited by bombarding $^{60}$Ni and $^{120}$Sn targets. The beams of radioactive ions, having energies of between 4.25 and 5.08 MeV.A, were provided by HIE-ISOLDE. The purpose of these measurements is to determine the intrinsic quadrupole and octupole...
The shell model nowadays can provide a comprehensive view of the atomic nucleus along the Segré chart. In fact, the regions around double-shell closures are a fantastic benchmark for nuclear structure studies, since they provide a direct source of information on the nucleon-nucleon effective interaction. A case of great interest is the study of the east region around the doubly magic...
Singly-magic nuclei in the vicinity of a doubly-magic core are in the scope of interest of modern nuclear physics. Their properties can be described by the few protons (or neutrons) situated outside of the doubly-magic core, therefore, they provide information on the basic ingredients of the shell model, such as single particle energies and two-body matrix elements. One of the most interesting...
Predictive power requires the ability to quantify theoretical uncertainties. While it is true that theoretical error estimates are difficult to obtain, the pursuit thereof plays a pivotal role in science. Reliable theoretical errors can help to determine to what extent a disagreement between experiment and theory hints at new physics, and they can provide input to identify the most relevant...
Over the last decade, the optical-readout time projection chamber developed in Warsaw has been applied to study a variety of rare and very exotic decay channels with emission of charged particles. The device, originally developed for studying two-proton radioactivity, turned out to be extremely well suited for studying delayed (multi) proton emission, in particular when low-energy protons are...
Type I X-ray bursts (XRB) are generally suggested as possible sites for the rp-process. These explosive events take place in binary systems in which a neutron star accretes hydrogen-rich material from a low-mass companion star. When the temperature and density in the accreted envelope become high enough to allow for a breakout from the hot CNO cycle, nucleosynthesis eventually proceeds near...
The heavy element nucleosynthesis is the area of research looking to predict and/or explain the observed abundances of nuclei heavier than iron. The proton rich nuclei are thought to be produced in the in hot environments such as supernovae via proton capture and the photodisintegration processes. But the observed abundances of lighter p-nuclei $^{92,94}$Mo and $^{96,98}$Ru are not reproduced...
ISOLDE has been a hub for the development of radioactive probe techniques and their application in solid state physics and other fields. In this talk, we review some recent highlights from the application of electron emission channeling and perturbed angular correlation spectroscopy to research on functional quantum materials: from well-established research activities on doping of...
Multiferroic Rashba semiconductors (MUFERS) are novel functional materials based on the coupling between ferromagnetism, ferroelectricity and Rashba-Zeeman effects [1]. Ge$_{1-x}$Mn$_x$Te, the model MUFERS, inherits the robust ferroelectricity and giant Rashba splitting of $\alpha$-GeTe, undergoing a ferroelectric phase transition at $T_C^{FE}$. Below the transition temperature, the cubic...
Magneto-electric multiferroics form an attractive class of materials, not only for the diversity of exciting fundamental phenomena they present but also by the potential technological applications foreseen. Among them are energy efficient memory devices, multiple state memories, as well highly sensible electrical-magnetic field sensors. Although the research in this area has increased...
Currently, intensive research in group III nitrides is focussed on improving the performance of commercial devices. This includes their heterostructures and/or alloys with other group III elements. Amongst the latter are ternary semiconductors such as Al$_{x}$Ga$_{1-x}$N, which are expected to give rise to unexpected photonic and magnetic functionalities when doped with magnetic ion species....
Titania TiO2 is a promising material candidate for batteries, water splitting and water purification. Its photocatalytical and Li-storage capabilities very much depend on the defect structure in the used titania. Hydrogenation and N-doping have proven to improve this defect structure in such a way that the mentioned properties are drastically improved [1–3].
With the help of nuclear solid...
Experiments at the Antiproton Decelerator of CERN compare properties of matter and antimatter at low energies for precision tests of fundamental symmetries and interactions.
Using either atoms made of antiprotons (antihydrogen or antiprotonic-helium) or singly trapped antiproton, AD experiments address a broad range of physics questions via a spectrum of different experimental techniques.
The...
In this talk, the recent experimental program and physics opportunities at the large acceptance VAMOS++ spectrometer in GANIL will be presented. The development of the new detection systems of the spectrometer and their performances will be reported. Further recent results ranging from prompt and prompt-delayed g-ray spectroscopy of isotopically identified fission fragments using the Advanced...
The SPES project is being built at the Legnaro National Laboratory of INFN. It is an interdisciplinary project, ranging over nuclear physics, nuclear medicine and materials science. SPES (SPES $\beta$) will provide a Radioactive Ion Beam facility for the study of neutron rich unstable nuclei of interest to nuclear physics and nuclear astrophysics research. At the same time ( (SPES $\gamma$),...
B. S. Cooper, H. A. Perrett, C. Ricketts, K. T Flanagan and the CRIS collaboration.
The CRIS technique (Collinear Resonance Ionisation Spectroscopy) has been shown to be an efficient method for accessing fundamental nuclear properties of exotic isotopes [1]. Currently, radioactive ion beams are produced via proton impact with a suitable target at the ISOLDE (Ion separator On-line) facility at...
The RadioFrequency Quadrupole cooler buncher (RFQcb or ISCOOL) is a permanent beam cooling installation on the High Resolution Separator (HRS) at ISOLDE. It is extensively used by many of the downstream experiments for beam preparation by reducing the transverse emittance and converting a DC beam into pulsed bunches.
An extensive investigation into the RFQcb bunching properties was carried...
Collinear resonant laser ionization spectroscopy is a powerful technique which can provide a unique insight in nuclear properties such as spin, electromagnetic moments and changes in mean-square charge radii from near doppler-free measurement of the hyperfine structure of exotic isotopes. This technique was recently used at the collinear resonant ionization spectroscopy (CRIS) beam line at...
The radiative capture reaction $^{13}$N(p,$\gamma$)$^{14}$O is an important reaction determining the transit from the Carbon-Nitrogen-Oxygen (CNO) cycle to the hot CNO cycle occurring in several astrophysical situations such as super-massive stars, novae etc. Since the direct measurement is difficult due to low cross section, Coulomb dissociation of $^{14}$O in the presence of a heavy target...
This work pertains to determining the spectroscopic quadrupole moment for the first 2+ state in 66Ge using “safe” Coulomb excitation measurements. Motivation to study 66Ge arises from the anomalous rotational behaviour of the high-lying first 2+ state observed in even-even isotopes in the A ~ 70 region [1]. Low-lying 0+ excited states have been suggested for even-even neutron-deficient nuclei...
In this talk, I will present the study of the decay of 8B into highly excited states of 8Be with the aim of determining the branching ratios. Our interest lies in the 2+ doublet at 16.6 and 16.9 MeV populated via β+ and electron capture (EC) respectively and also the so far unobserved EC-delayed proton emission via the 17.640 MeV state, that has a theoretical branching ratio of 2.3·10-8. The...
The experiments at the SEC and IDS with segmented silicon detectors utilize a VME-based DAQ with between 100 and 300 channels, typically. The achievable acquisition rates of modern triggered nuclear physics experiments are heavily dependent on the readout software. This contribution presents a novel readout scheme that minimizes the deadtime associated with data readout, thus lowering the...
The interest in Be in GaN stems from the challenge to understand why it is technologically feasible to dope this wide band gap semiconductor p-type with Mg, while this does not work for Be. While theory has actually predicted an acceptor level for Be that is shallower than Mg [1,2], it was also argued that Be would not be a suitable acceptor because its amphoteric nature, i.e. its tendency...
Collinear laser spectroscopy (CLS) is a powerful technique to probe the structure information of the ground and long-lived isomeric states by measuring their nuclear spins, moments and charge radii [1, 2, 3]. Over the last decade, this technique has been intensively employed for the study of the exotic isotopes of the Ni region, namely around the major proton shell closure at Z = 28 and...
Fusion reactions can play an important role in the dynamics of weakly-bound exotic nuclei at sub-Coulomb energies.
However, these measurements are usually difficult to perform due to the low value of cross sections and beam intensities.
In this contribution we discuss the advantages and limitations of applying radiochemical techniques using recent data
on the sub-barrier fusion of the...
The IS559 experiment is the first ever attempt of utilising the Oslo Method with a radioactive beam in inverse kinematics reactions. A $^{66}\mathrm{Ni}$ beam with 4.5 MeV/u hit a deuterated polyethylene target for a total of ≈ 10 days. The ultimate goal of the experiment is to look for particle-gamma coincidences from the d($^{66}\mathrm{Ni}$,p)$^{67}\mathrm{Ni}$ reaction, reconstructing the...
L. Barber [1], D. M. Cullen [1], B. S. Nara Singh [1], M. Giles [1], M. J. Taylor [1], P. Papadakis [2], E. Parr [2], J. Heery [2], T. Grahn [3], P. T. Greenlees [3], H. Badran [3], R. Julin [3], S. Juutinen [3], J. Konki [3], M. Leino [3], J. J. Pakarinen [3], J. Partanen [3], P. Rahkila [3], M. Sandzelius [3], J. Saren [3], J. Sorri [3] and J. Uusitalo [3].
[1] University of Manchester,...
11-Be is the neutron - rich nucleus expected to be a β-delayed proton emitter. The (very mall) branching ratio for this exotic decay mode (∼ 10e−6 ) was obtained through indirect
observations based on accelerator mass spectrometry [1, 2] and resulted to be about two
orders of magnitude larger than predicted by theory [3]. The direct measurement of the
delayed proton emission probability and...
Due to its high precision, accuracy, and resolution, Collinear Laser Spectroscopy (CLS) is an important experimental technique to access nuclear spins, electromagnetic moments, and mean square charge radii of short-lived radionuclides and hence provides insight into the nuclear shell structure [1]. However, to experimentally probe the most exotic nuclides, which can only be produced with low...
High entropy alloys are multicomponent alloys, which consist of four or more elements in equiatomic or nearly equiatomic concentrations. These materials are hypothesized to show significantly decreased self-diffusivities. The understanding of the diffusion kinetics in HEAs is of fundamental significance, however the present knowledge is limited to several interdiffusion investigations on the...
The strength function $ S_{\beta}(E) $ governs [1,2] the nuclear energy distribution of elementary charge-exchange excitations and their combinations like proton particle $({\pi}p)$-neutron hole $({\nu}h)$ coupled into a spin-parity $I^{\pi}$ : $[{\pi}p \otimes {\nu}h]I^{\pi}$ and neutron particle $({\nu}p)$-proton hole $({\pi}h)$ coupled into a spin-parity $I^{\pi} : [{\nu}p \otimes...
For certain combination of protons and neutrons an appearance of reflection asymmetry is expected. In particular, the experimentally determined E3 strengths as a function of the neutron number are peaked around N~88 and N~134. Many theoretical approaches have been applied to describe the regions of enhanced octupole collectivity and its experimental signatures, such as parity doublets in...
Over the last years the advance in experimental techniques allowed to refine the experimental knowledge on $^{133}$Sn, which is a key nucleus to deduce neutron single-particle (SP) energies above the doubly magic $^{132}$Sn core. The different adopted techniques allowed to obtain mutually consistent information about SP energies for $\nu p_{3/2}$, $\nu p_{1/2}$, $\nu h_{9/2}$ and $\nu f_{5/2}$...
Targeted Radionuclide Therapy (TRT) and diagnostics are currently the most intensively developing fields of nuclear medicine as they allow the very precise imaging of tumors (or other targeted tissues), and the minimization of healthy tissue damage during medical therapy. TRT relies on the labeling of a radionuclide to a targeting vector – a biomolecule that has a high affinity to...
In the atomic nucleus, the interplay between single-particle motion, collectivity and
pairing is seen as a rich tapestry of shape coexisting states and exotic excitations, often associated with so called intruder states. One region where this shape coexistence phenomenon is especially prevalent is in the very neutron-deficient nuclei close to Z=82 with a neutron number close to the mid-shell...
In December 2017 we recorded the first beta-NMR signals of 26Na in liquid samples [Kow18]using the Bio Beta-NMR setup at the VITO beamline [Kow17, Gin18]. 2018 has seen many beamline upgrades including a new charge exchange cell [Gin18], a home-build vacuum-compatible NMR magnetometer, a new magnet giving better homogeneity and higher field strength, a new measurement chamber and a temporal...
It is well known that there is a serious anomaly between the observed and Big Bang Nucleosythesis predicted abundance of $^{7}$Li. Since the $^{7}$Li abundance is known to be intimately related to the production and destruction of $^{7}$Be, it is pertinent to study reactions involving $^{7}$Be. An experiment measuring the transfer reaction $^7$Be(d,p)$^8$Be* at E = 5 MeV/A (IS 554) at...
Dielectronic Recombination (DR) is a resonant process that describes the capture of an electron by a (highly charged) ion, occurring at sharply defined collision energies. In an electron beam ion source, where charge breeding is achieved through successive electron impact ionisation, DR transitions can be selectively driven by adjusting the electron beam energy. The increased recombination...
Molecular beams injected into the ISOLDE Radio-Frequency Quadrupole cooler and buncher (RFQcb), ISCOOL, have been studied under varying conditions using the new Time-of-Flight detector at ISOLDE.
When a beam of molecules is injected into the RFQcb and the molecules interact with the buffer gas collisional dissociation processes may occur. In this study, two different beams of molecules,...
The WISArD (Weak Interaction Studies with Argon Decay) experiment aims to determine the beta-neutrino angular correlation (a$_{\beta\nu}$) in the super-allowed Fermi decay of $^{32}$Ar. The latter decays are sensitive probes to a possible scalar contribution in the weak interaction model. Deviation from the expected theoretical value will point to physics beyond the standard model.
The...
The structure of the odd-odd 232Ac nucleus, produced in the β– decay of 232Ra, was investigated through γ-ray spectroscopy at the ISOLDE Decay Station at ISOLDE, CERN. A radioactive beam of 232Fr was implanted in the IDS. The γ-rays originating from the β – decay chain 232Fr - 232Ra - 232Ac - 232Th were registered using a mixed array consisting of 4 HPGe Clover and 2 LaBr3(Ce) detectors...
The ISOLDE facility uses about 50-60% of all the CERN protons on its two targets to produce radioactive isotopes for physics research. Most of these protons go through the ISOLDE targets into the dumps, without any interaction, only having their energy slightly reduced. To "recycle" these protons, the MEDICIS facility (MEDical Isotopes Collected from ISOLDE) was created to fulfill the demand...
Terbium is a unique element, as it provides a quadruplet of radionuclides suited for diagnostics and therapy in nuclear medicine [1]. Much success has been gained from the PSI-ISOLDE collaboration, with the collection and purification of 149Tb (α-emitter, T1/2 = 4.1 h – for potential therapy), used for preclinical therapy studies [2] and PET imaging [3], and 152Tb (β+-emitter, T1/2 = 17.5 h –...
Collinear laser spectroscopy (CLS) is a powerful tool to access nuclear ground state properties such as nuclear spins, electromagnetic moments and mean-square charge radii of short-lived radionuclides far from stability with high precision and accuracy [1,2]. Performing CLS with fast beams (>30 keV) provides an excellent spectral resolution approaching the natural linewidth [1]. However,...
The ISOLDE target and ion source units are manufactured on demand, following the specifications implied the physics schedule. The production of each target typically takes few days, but can also take up to weeks, depending on the complexity. After the units are manufactured, they are tested at the ISOLDE OFF-LINE mass separator before they are delivered to ISOLDE for irradiation. The OFF-LINE...
CERN’s long shutdown periods provide an ideal window of opportunity to revise and consolidate the ISOLDE Facility. The Long Shutdown period 2 (LS2) starts in December 2018 and terminates in December 2020 with protons to ISOLDE, under normal operating conditions, expected in April 2021. ISOLDE will use this time to prepare the facility for the next operational period and to address the backlog...
The Resonance Ionization Laser Ion Source (RILIS) at ISOLDE continued its status as the most frequently used ion source at the facility in 2018, providing laser-ionized beams of 14 elements over 20 experimental runs. Additional beams were provided during a dedicated target and ion source development period. Highlights from the 2018 on-line period will be presented.
Experimentally, the...
Most commonly, ISOLDE uses positively charged ion beams produced by a variety of ion sources such as the positive surface ion source, the Resonance Ionization Laser Ion Source (RILIS) or the Forced Electron Beam Induced Arc Discharge (FEBIAD) ion source. In recent years, the availability of negative ion beams at ISOLDE was re-established and the development program of negative ion sources was...
H. Heylen$^1$, S.W. Bai$^2$, J. Billowes$^3$, M.L. Bissell$^3$, K. Blaum$^4$, B. Cheal$^5$, C.S. Devlin$^5$, R.F. Garcia Ruiz$^1$, W. Gins$^6$, C. Gorges$^7$, P. Imgram$^7$, A. Kanellakopoulos$^6$, S. Kaufmann$^7$, K. König$^7$, A. Koszorús$^6$, J. Krämer$^7$, S. Lechner$^{1,8}$, B. Maass$^7$, S. Malbrunot-Ettenauer$^1$, R. Neugart$^{4,9}$, G. Neyens$^{1,6}$, W. Nörtershäuser$^7$, T....
The ISOLDE Decay Station (IDS) [1] has been a permanent experiment used for studies of low-energy nuclear physics at the CERN-ISOLDE facility, since 2014. The core of the setup consists of four, high-efficiency, clover-type germanium detectors and a tape transportation system. These can be coupled to a number of ancillary detector arrays, used for alpha/beta/gamma spectroscopy, neutron...
With a proton hole in the Z = 50 shell closure, the indium isotopic chain (Z = 49) offers a compelling scenario to explore the evolution of nuclear-structure properties in the neighbourhood of the doubly-magic isotopes 100Sn (Z, N = 50) and 132Sn (N = 82).
This contribution will present two recent successful campaigns to measure the hyperfine spectra of the neutron-deficient neutron-rich...
The nucleus of $^8$He is characterized by the largest neutron-to-proton ratio among all known particle-stable nuclei. Beta decay of $^8$He has been investigated by Björnstadt et al. [1] and Borge et al. [2, 3] where $\beta$-delayed γ-ray, neutron and triton spectra were measured. In this contribution, the results of the new study of $\beta$-delayed neutron decay branch of $^8$He will be...
At the Radioactive Isotope Beam Factory in-beam gamma-ray spectroscopy experiments take advantage of the wide range of radioactive ion beams produced by the projectile fragmentation and fission. Isotopes of interest are separated by the BigRIPS fragment separator and guide to a secondary reactions target. Reaction residues are identified either in the ZeroDegree spectrometer or with the...
We have measured several 2S-2P transitions in muonic hydrogen (μp), muonic deuterium (μd) and muonic helium ions (μ3He, μ4He). From muonic hydrogen we extracted a proton charge radius 20 times more precise than obtained from electron-proton scattering and hydrogen high-precision laser spectroscopy but at a variance of 7σ from these values. This discrepancy is nowadays referred to as the...
The high-resolution, large-acceptance neutron time-of-flight spectrometer NeuLAND is the new neutron detector being developed for
the R3B setup (Reactions with Relativistic Radioactive Beams) at
FAIR. NeuLAND is dedicated to the detection of high-energy neutrons
up to 1GeV. In this talk, I will report on the design concept and the status of construction. An overview over the experimental...
The reduced transition probability or $B(E2;0^+_1\rightarrow 2^+_1)$ value and the spectroscopic quadrupole moment of the first excited 2$^{+}_{1}$ state, $Q_{_S}(2^{+}_{1})$, at 1.633 MeV in $^{20}$Ne have been determined at safe energies using the {\small TIGRESS} and AFRODITE arrays at TRIUMF and iThemba LABS, respectively. Large values of $B(E2;0^+_1\rightarrow 2^+_1)=22.4(16)$ W.u. and...
The 2018 ISOLDE high energy Physics campaign started last July, immediately after Phase 2B of the HIE-ISOLDE project was completed. Since then, multiple stable and Radioactive Ion Beams (RIBs) have been delivered to the three different experimental stations (Miniball, ISS and the Scattering chamber) and fourteen experiments have been conducted. The main issues and the operational highlights...
This presentation will give you an overview of the foreseen maintenance and modifications during the Long-Shutdown 2 period related to the ISOLDE post-accelerator REX and HIE ISOLDE as well as the High Energy Beam Transferlines.
Several aspects of optimisation or development towards a more complete understanding of the REX/HIE-ISOLDE linear accelerator will be presented.
We will first demonstrate the possibility to map a spectrum of contamination from residual gas ions, on a wide mass-to-charge ratio range, helping on the anticipation of the ion beam purity. Additionally, an effort for the optimisation of the ion...
Within work-package 2 of the MEDICIS-Promed ITN we study the possibilities of using a radioactive therapy beam in hadron therapy. In particular, 11C (β+ emitter, t1/2=20.3 min) is investigated as it has excellent properties for both on-line and off-line PET imaging, which can be used for dose verification. While ions are produced abundantly in conventional hadron therapy with stable carbon, it...
Key in the establishment of the traditional concepts of nuclear shells, binding-energy studies were also pivotal to the early realization of the demise of the traditional shell closures away from stability [1]. Extensive effort has followed to examine the classical signatures for magicity in exotic nuclei and more than three decades later, the robustness of all major shell closures has been...
I will discuss which kind of new phenomena can be probed through precision measurements in nuclear processes. Using a model-independent description I will discuss the interplay between the different experiments and which ones are the most sensitive and promising. Finally I will analyze the synergy with searches at high-energy colliders, such as the LHC, and with other electroweak precision observables.
Extracting the shape of a nucleus in its ground state when its spin is less than 1 is not possible by a direct measurement of the quadrupole moment. This limits the sources of information available for the study of the ground state shapes of even-even nuclei. Common alternatives are the extraction of the information from electromagnetic transitions along the ground state band or measurements...
A dedicated and world-wide unique program to study $\beta$-delayed fission ($\beta$DF) is being performed by our collaboration since a decade ago at the ISOLDE (CERN), e.g. [1,2,3]. In $\beta$DF, the mother nucleus undergoes $\beta$ decay to excited state in the daughter nucleus with the energy comparable to the fission barrier height and the daughter nucleus then fissions. The excitation...
