Joint Annual Meeting of ÖPG and SPS 2021

Session

Nuclear, Particle- & Astrophysics

31 Aug 2021, 13:30

121. 【301】Flavour anomalies in b -> sll meson decays: a review

Elena Graverini (EPFL - Ecole Polytechnique Federale Lausanne (CH))

31/08/2021, 13:30

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

Flavour physics studies the different generations of fermions in the Standard Model (SM). The origin of flavour is, as of today, completely unknown. Flavour physics can inform efforts to produce a new theory beyond the SM, explaining phenomena such as dark matter and antimatter disappearance.
Recently, the LHCb experiment uncovered anomalies in lepton flavours. Hints of violation of “lepton...

220. 【302】Lepton flavour universality tests in charged-current b-quark decays

Annarita Buonaura (Universität Zürich (CH))

31/08/2021, 13:45

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The Lepton Flavour Universality (LFU) anomalies are currently one of the hottest topics in the particle physics community. A combination of recent results from LHCb, Belle and BaBar from charged-current decays of B mesons have shown a discrepancy from the Standard Model prediction of ~3 σ. This talk will review the latest lepton universality tests with b → clν decays and present the progresses...

330. 【303】Discovering Lepton Flavour Universality Violating New Physics

Andreas Crivellin (Universitaet Zuerich (CH))

31/08/2021, 14:00

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

While the LHC has not discovered any new particles directly yet, hints for the violation of lepton flavour universality (satisfied within the SM) accumulated in recent years. In particular, deviations from the SM predictions were observed in semi-leptonic B decays (b->sll and b->ctau), in the anomalous magnetic moment of the muon (g-2), in leptonic tau decays and di-electron searches....

293. 【304】On $R_K$ and the global significance of new physics in $b\to s\ell \ell$ decays

Davide Lancierini (Universitaet Zuerich (CH))

31/08/2021, 14:15

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

Ratios of branching fractions such as $R_K=\mathcal{B}(B^{+}\to K^{+}{\mu }^{+}{\mu }^{-})/\mathcal{B}(B^{+}\to K^{+}{e}^{+}{e}^{-})$ are clean probes of lepton flavour universality (LFU) violation. LHCb published the most accurate measurement of this observable up to date, yielding a value $3.1\sigma$ away from the Standard Model prediction, providing the first evidence of LFU...

175. 【305】A new approach in the search for New Physics in b→sl+l- decays

Michele Atzeni (Universitaet Zuerich (CH))

31/08/2021, 14:30

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

Recent studies of rare semileptonic decays of beauty mesons reported some intriguing discrepancies with the SM predictions, which seem to form a coherent pattern. Of particular interest are the angular observable P5' of the B→K*μ+μ- decay and the suppression of the muon channel in the ratios of branching fractions of B+→K+μ+μ− to B+→K+e+e− transitions.
The proposed research aims to perform an...

381. 【306】Angular analysis of $B^0\to K^{\ast 0}{e}^{+}{e}^{-}$ decays at LHCb

Zhenzi Wang (Universitaet Zuerich (CH))

31/08/2021, 14:45

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The family of decays mediated by $b\to s{\ell }^{+}{\ell }^{-}$ transitions ($\ell =\mu ,e$) provides a rich laboratory to search for physics beyond the Standard Model. In recent years, LHCb has found hints of deviations from theoretical predictions notably in lepton flavour universality (LFU) testing branching fraction ratios (\textit{i.e.} $R_K$ and $R_{K^{\ast 0}}$), as well as angular...

277. 【307】Test of lepton flavour universality in $B^{+}\to K^{+}{l}^{+}{l}^{-}$ decays in high dilepton invariant mass squared region

Mr Vadym Denysenko (Universitaet Zuerich (CH))

31/08/2021, 15:00

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The recently updated value of the ratio of branching fractions $R_K=\mathcal{B}(B^{+}\to K^{+}{\mu }^{+}{\mu }^{-})/\mathcal{B}(B^{+}\to K^{+}{e}^{+}{e}^{-})$ that has been calculated for a dilepton invariant mass squared range $q{}^2\in (1.1{\mathrm{GeV}}^2,6.0{\mathrm{GeV}}^2)$ is in tension with the Standard Model prediction at the level of 3.1 $\sigma$. I will discuss a complementary study in the high $q\mathrm{^2 >...

245. 【308】Search for New Physics in baryons decay at LHCb

Martina Ferrillo (Universitaet Zuerich (CH))

31/08/2021, 15:15

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

New exciting results have been published by the LHCb experiment on the Lepton Flavour Universality (LFU), especially in rare loop-mediated processes. To further corroborate or discard New Physics (NP) scenarios, additional testing is needed at fundamental tree-level processes: baryonic semi-leptonic decays provide a unique means to test for LFU at the LHCb, given e.g. their production...

42. 【309】Search for Lepton Flavour Universality Violation at CMS

Federica Riti (ETH Zurich (CH))

31/08/2021, 15:30

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

Lepton flavour universality tests, that could reveal hints for new beyond the Standard Model phenomena, can be pursued with data collected by the CMS experiment at a center of mass energy of 13 TeV. During the talk, a specific measurement will be presented, with focus on the approaches and methodology pursued, showing the performances involved towards the finalisation of the measurement.

300. 【310】Highlights from CP-violation in B-decays and Lepton Flavour violation measurements with the ATLAS experiment

Emmerich Kneringer (University of Innsbruck (AT))

31/08/2021, 15:45

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

Non standard model contributions to CP-violation are required to explain the matter-antimatter asymmetry in the universe. To challenge this ATLAS is measuring CP-violation to high precision in decays of the Bs meson. A dominant source of systematics is detector alignment, which has to be under control. Moreover, a test of the universality of tau and muon lepton couplings in W-boson decays from...

14. 【311】Combined Constraints on First Generation Leptoquarks

Luc Schnell (Uni Zürich & PSI Villigen)

31/08/2021, 16:30

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

We present a combined analysis of low energy precision constraints and LHC searches for leptoquarks which couple to first generation fermions. Considering all ten leptoquark representations, we study at the precision frontier the constraints from $K\to \pi \nu \nu$, $K\to \pi e^{+}{e}^{-}$, $K^0-{\overline{K}}^0$ and $D^0-{\overline{D}}^0$ mixing, as well as from experiments searching for parity violation (APV and...

168. 【312】Global Analysis of Leptophilic Z' Bosons

Fiona Kirk (University of Zurich, PSI)

31/08/2021, 16:45

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

One of the most minimal and most studied extensions of the Standard Model of particle physics is the $Z^{\prime }$ boson. The LHC bounds on $Z^{\prime }$ bosons that couple to quarks are very strong, models involving leptophilic $Z^{\prime }$ bosons are, however, much less constrained.
We perform global fits to leptophilic $Z^{\prime }$ models, putting bounds on the $Z^{\prime }$ couplings to leptons, and show correlations between...

115. 【313】QCD Constraints on the Hadronic Light-by-Light Contribution to the Muon g − 2

Jan Lüdtke (University of Vienna)

31/08/2021, 17:00

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The new results by the Fermilab g-2 Collaboration have consolidated the long-standing discrepancy between the Standard Model (SM) prediction and the experimental measurement of the muon anomalous magnetic moment, which is traditionally considered a harbinger for New Physics. I will discuss one specific part of the SM evaluation, namely the hadronic light-by-light contribution (HLbL), which is...

133. 【314】Holographic QCD and the anomalous magnetic moment of the muon

Josef Leutgeb (Vienna University of Technology)

31/08/2021, 17:15

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The estimated error of the standard model prediction for the anomalous magnetic moment of the muon comes almost exclusively from hadronic vacuum polarization and hadronic light-by-light scattering, where the latter is dominated by exchanges of neutral pseudoscalars and axial vector mesons. Using holographic QCD we are able to calculate these contributions and to solve the problem of most...

451. 【329】A relevant correction for direct measurement of electron's g-factor

Benjamin Koch (Technical University of Vienna)

31/08/2021, 17:30

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

203. 【315】Study of a very rare decay with multiple leptons in the final state at the LHCb experiment

Sonia Amina Bouchiba (EPFL - Ecole Polytechnique Federale Lausanne (CH))

31/08/2021, 17:45

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

Particles decays with muons coming from a virtual photon in the final state are theoretically promising. In particular the discarding of helicity suppression for such channel is an advantage for leptonic flavour universality (LFU) testing in very rare $b$ hadron decay modes. The abundant channel $B^{+}\to K^{+}J/\psi {\gamma }^{\ast }(\to {\mu }^{+}{\mu }^{-})$ can be studied with the available dataset...

2. 【316】Measuring the decay $B^{+}\to {\rho }^0{\mu }^{+}{\nu }_{\mu }$ at LHCb

Veronica Soelund Kirsebom (EPFL - Ecole Polytechnique Federale Lausanne (CH))

31/08/2021, 18:00

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

A long standing tension between measurements of the CKM matrix element $V_{\mathrm{u}\mathrm{b}}$ in inclusive and exclusive semileptonic decays could be due to new physics.
By using data from the LHCb experiment, we are performing a measurement of $V_{\mathrm{u}\mathrm{b}}$ from the decay $B^{+}\to {\rho }^0{\mu }^{+}{\nu }_{\mu }$. This talk will focus on the steps toward extracting the signal yield from data. This...

55. 【317】Amplitude analysis of B -> K pi pi gamma decays at LHCb

Marie Bachmayer (EPFL - Ecole Polytechnique Federale Lausanne (CH))

31/08/2021, 18:15

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The photon polarisation in $b\to s\gamma$ transitions is predicted to be predominantly left handed in the Standard Model. Contributions from New Physics processes could significantly enhance the right-handed component. The $B\to K\pi \pi \gamma$ decay is a $b\to s\gamma$ transition and is sensitive to the polarisation of the photon through interference between the...

393. 【318】Measuring $\mathcal{B}(B^0\to K^{\ast 0}{\tau }^{+}{\tau }^{-})$ via the double-loop process $B^0\to K^{\ast 0}{\tau }^{+}{\tau }^{-}(\to {\mu }^{+}{\mu }^{-})$

Martin Andersson (Universitaet Zuerich (CH))

31/08/2021, 18:30

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

Recent measurements of $B$-meson decays show a consistent pattern of tensions between measured observables and Standard Model (SM) predictions. These tensions are referred to as the flavour anomalies. To understand the source of these anomalies, measurements of $b\to$$s{\tau }^{+}{\tau }^{-}$ processes are paramount, as many New Physics explanations favour enhancements in this mode. Of particular...

404. 【319】On the difference between the FOPT and CIPT approach for the hadronic tau decay rate

Christoph Regner (University of Vienna)

31/08/2021, 18:45

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The discrepancy between the FOPT and CIPT approaches for the hadronic tau decay rate is a debated subject and constitutes the major theoretical uncertainty for strong coupling determinations. We show that the discrepancy can be analytically understood since the Borel representations for FOPT and CIPT do not agree. This implies that the OPE corrections are different for both approaches and that...

412. 【321】Large charge, semiclassics and superfluids

Dr Gabriel Francisco Cuomo (Stony Brook University)

01/09/2021, 14:00

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

In quantum field theory, states with large quantum numbers under the conserved charges of the theory are generically amenable to a semiclassical description. This observation underlies some recent progress in the study of the spectrum of operators with large internal charge in strongly coupled conformal field theories. I will review these results and show how similar ideas can be used to...

413. 【322】Glueballs and Gauge / Gravity Duality

Frederic Brünner (TU Wien)

01/09/2021, 14:30

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

Glueballs, bound states of gluons, can be studied by mapping certain limits of strongly coupled gauge theories to higher-dimensional theories of weakly coupled gravity. This approach has the advantage of permitting computations of glueball decay rates for processes involving mesons as final states. I will give an overview of the calculation of glueball decay patterns in the...

414. 【323】Measurement of the prompt χ_c1 and χ_c2 polarizations at CMS

Thomas Madlener (Deutsches Elektronen-Synchrotron (DESY))

01/09/2021, 14:53

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The process of hadron formation via the strong force is not yet fully understood. Quarkonia, bound states of a heavy quark and its anti-quark are ideal probes to study this process. Theoretically the production of quarkonia can be described by the Non-Relativistic Quantum Chromodynamics (NRQCD) framework. The factorization approach that is employed by the framework relies on experimental...

83. 【324】Measurement of the Branching Fraction and Kinematic Variables of B0 -> D*- l+ nu_l using the Belle II data

Daniel Dorner (Austrian Academy of Sciences (AT))

01/09/2021, 15:15

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The goal of this analysis is to make a precise measurement of the magnitude of the element |$V_{cb}$| of the Cabibbo–Kobayashi–Maskawa matrix based on B-decays to the exclusive final state $D^{\ast -}{l}^{+}{\nu }_l$. We will explain how this new measurement addresses several limitations of previous determinations and will help to clarify the experimental status of |$V_{cb}$|. The first steps are to...

329. 【341】DARWIN - a next-generation observatory for dark matter and neutrino physics

Laura Baudis (University of Zurich)

01/09/2021, 15:15

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

Two open questions in physics are the nature of dark matter and the fundamental nature of neutrinos. DARWIN is a next-generation experiment aiming to reach a dark matter sensitivity limited by the cosmic neutrino background. The core of the detector will be a TPC with 40 t of liquid xenon as dark matter target. The large xenon mass, the ultra-low radioactive background and the low energy...

85. 【325】Measurement of the Cabibbo-Kobayashi-Maskawa matrix element |Vcb| using the decay B− -> D0 l− nu_l at Belle II

Philipp Horak (Austrian Academy of Sciences (AT))

01/09/2021, 15:30

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

A long-standing discrepancy in flavour physics is observed in the determination of the CKM elements |Vcb| and |Vub|. For |Vcb|, a combined tension of about 3σ is seen between different methods of determination. We revisit the decay B- -> D0 l- nu_l using data of the Belle II experiment to clarify the experimental status of this parameter. In addition to a measurement of the decay branching...

38. 【326】Measurement of q^2 moments in inclusive B -> Xclnu decays and determination of the Cabibbo-Kobayashi- Maskawa matrix element Vcb at Belle II

Manca Mrvar (Austrian Academy of Sciences (AT))

01/09/2021, 15:45

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

A new theoretical framework based on the Operator Product Expansion allows to extract the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element Vcb with O(1/mb^4) precision. This approach requires also the measurement of the moments of the q^2 distribution, the sum of the charged lepton and neutrino 4-momenta squared, which are unmeasured up to now. The |Vcb| parameter will be determined...

56. 【342】The upgraded low-background germanium counting facility Gator for high-sensitivity $\gamma$-ray spectrometry

Mr Alexander Bismark (University of Zurich)

01/09/2021, 15:45

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The Astroparticle Physics Group at the University of Zurich operates a high-purity germanium (HPGe) spectrometer (Gator) in a low-background environment underground at the Laboratori Nazionali del Gran Sasso (LNGS) in Italy. The 2.2 kg $\gamma$-ray spectrometer is one of the world’s most sensitive HPGe detectors with an integrated count rate of (86.2 $\pm$ 0.7) events/(day kg) in the energy...

60. 【327】Measurement of the VH production mode in the H→bb decay channel in proton-proton collision data at √s = 13 TeV

Christina Reissel (ETH Zurich (CH))

01/09/2021, 16:00

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

We present the measurement of Higgs boson production in association with a W/Z boson considering only events where the Higgs boson decays into a bottom quark-antiquark pair. The talk focuses on the analysis of 41.5/fb collision data taken by the CMS experiment in 2017 at a center of mass energy of 13 TeV. The talk aims at summarizing the analysis methods as well as presenting potential areas...

80. 【343】POLAR-2: Towards a Large Scale Gamma-ray Polarimetry

Johannes Hulsman (Universite de Geneve (CH))

01/09/2021, 16:00

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

Gamma-ray bursts have been studied for over 50 years; primarily through their spectral and temporal profiles. However, their physics is sometimes impossible to answer without the addition of polarization information. From recent instrument observations, it was understood that in combination with a long mission, detailed temporal and energy resolved analyses are necessary to further constrain...

324. 【328】Identifying the Higgs boson production in the ttH(bb) channel using quantum classifiers

Vasileios Belis (ETH Zurich (CH))

01/09/2021, 16:15

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

We have developed two quantum classifier models for the $t\overline{t}H(b\overline{b})$ classification problem, both of which fall into the category of hybrid quantum-classical algorithms for Noisy Intermediate Scale Quantum devices. Our results serve as a proof of concept that Quantum Machine Learning (QML) methods can have similar or better performance, in cases of low number of training samples, with...

91. 【344】Invisible Nucleon Decays in the XENON1T experiment

Giovanni Volta (University of Zurich)

01/09/2021, 16:15

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

In the Standard Model (SM) of particle physics the conservation of baryon number (B) is an empirically observed symmetry. However, B could be an approximate symmetry of Nature, and violated by small amounts as predicted by many SM extensions. Using XENON1T/nT data we can search for inclusive radiogenic nucleon decays: model-independent $N\to X+\mathit{\text{anything}}$ channels, also...

338. 【331】High-Field Magnet Development for Accelerators in CHART MagDev

Bernhard Auchmann (PSI/CERN)

01/09/2021, 17:00

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The MagDev project in the CHART framework develops magnet technology in support of the European Strategy for Particle Physics, in particular the international High-Field Magnet (HFM) program. The research spans fast-turnaround technology development, the research of numerical tools, innovative magnet design, manufacturing-process development, and the construction and testing of technology...

98. 【351】LEGEND - The Large Enriched Germanium Experiment for Neutrinoless Double Beta Decay

Yannick Müller (University of Zurich)

01/09/2021, 17:00

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

LEGEND is the successor of the GERDA and MAJORANA DEMONSTRATOR experiments searching for neutrinoless double beta decay. An observation would imply both the Majorana nature of neutrinos and the violation of lepton number conservation, with important consequences for the understanding of the neutrino mass scale, and the matter-antimatter asymmetry in the Universe. The first experimental phase,...

371. 【332】High Temperature Superconducting Undulator Development at PSI/CHART

Xiaoyang Liang (PSI - Paul Scherrer Institut)

01/09/2021, 17:15

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

Short period undulators are the key components of future compact accelerator-based sources of X-rays. The in-vacuum and cryogenic permanent magnet technology and electromagnetic low-temperature superconducting undulators are state of the art. In this talk, we present an alternative approach based on bulk high-temperature superconductors, which combines the advantages of an electromagnetic...

156. 【352】Cosmic ray Sub-Iron and Nickel nuclei fluxes measurement from AMS-02 data

Erwan Robyn (Universite de Geneve (CH))

01/09/2021, 17:15

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The Alpha Magnetic Spectrometer is operating on the International Space Station since May 2011. So far, it has collected more than 170 billion cosmic-ray events and measured the fluxes of cosmic-ray nuclei up to Silicon (Z=14) and lately of Iron (Z=26) with unprecedented precision providing new and crucial information for cosmic-ray models . In this contribution, I will present the ongoing...

415. 【333】Developing a new collaborative software framework for FCC-ee simulations

Felix Simon Carlier (EPFL)

01/09/2021, 17:30

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The FCC-ee is one of the main candidates to succeed the High Luminosity LHC at the forefront of particle colliders. The unprecedented energy and luminosity goals in the FCC-ee require extensive simulation campaigns to validate the design. While many different codes exist that address key aspects of the FCC-ee project, it is often complicated if not impossible to combine these and merge...

166. 【353】The XENONnT detector and physics programme

Mr Ricardo Peres (University of Zurich)

01/09/2021, 17:30

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The XENONnT detector recently started its commissioning phase at Laboratori Nazionali del Gran Sasso. Utilizing 5.9 tonnes of liquid xenon (LXe) as active target and designed for a high level of background reduction, it will greatly improve the results of its predecessor, XENON1T. Although primarily a dark matter detector for direct detection of Weakly Interacting Massive Particles, other...

383. 【334】Precision Luminosity Measurement at the LHC

Joanna Wanczyk (EPFL - Ecole Polytechnique Federale Lausanne (CH))

01/09/2021, 17:45

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The goal of the study is to reach 1% uncertainty - the most precise luminosity measurement for high pile-up pp machine. The accumulated experience and detector upgrades give a unique opportunity to improve the measurement during Run 3 and prepare for demanding HL-LHC conditions. Better luminosity precision is required to minimize its impact on numerous particle physics measurements.
The focus...

303. 【354】Cosmic-ray propagation under consideration of spatially resolved source distributions

Ms Julia Thaler (University of Innsbruck)

01/09/2021, 17:45

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

Numerical simulations for cosmic-ray propagation through the Galaxy are important e.g. for understanding the diffuse $\gamma$-ray emission seen by different experiments. Up to now, the source distributions used as input for such simulations are often relying on analytical functionals rather than individual, observation-based sources.
Here, we investigate the impact of cosmic-ray source...

370. 【335】Ion Laser InterAction Mass Spectrometry – providing utmost isotope abundance sensitivity

Dr Martin Martschini (University of Vienna - Faculty of Physics - Isotope Physics)

01/09/2021, 18:00

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

Accelerator Mass Spectrometry (AMS) is the technique of choice for the detection of environmental levels of long-lived radionuclides with typical relative abundances of 10${}^{-12}$ to 10${}^{-16}$. Interferences from stable isobars however used to restrict the applicability of this method to selected nuclides. The novel Ion Laser InterAction Mass Spectrometry (ILIAMS) technique at the Vienna...

315. 【355】Search for astrophysical sources of neutrinos with IceCube

Francesco Lucarelli (Universite de Geneve (CH))

01/09/2021, 18:00

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

IceCube, a large telescope of high-energy astrophysical neutrinos, has significantly contributed to our understanding of the Universe. After the discovery of a diffuse flux in 2013 and the detection of a high-energy event coincident with a flaring blazar in 2017, hints of potential sources are now being unveiled by recent analyses. Here we focus on the results of a time-integrated and a...

386. 【336】Relative Formation Probabilities for Fluoride and Oxyfluoride Anions Containing U, Np, Pu and Am in Accelerator Mass Spectrometry Measurements at VERA

Andreas Wiederin (University of Vienna, Faculty of Physics - Isotope Physics)

01/09/2021, 18:15

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The relative formation probabilities for a range of (oxy-)fluoride molecular anions containing uranium, neptunium, plutonium, and americium during the sputtering process in a Middleton type AMS ion source from an iron oxide matrix mixed with PbF${}_2$ have been investigated at VERA. Identifying this distribution is important for the separation of U and Np isobars via element selective...

296. 【356】UHECR Acceleration in FR-0 Jetted Active Galaxies

Dr Lukas Merten (University of Innsbruck)

01/09/2021, 18:15

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

Fanaroff Riley (FR) 0 radio galaxies form a low luminosity extension of the well-established ultrahigh energy cosmic ray (UHECR) accelerators FR-1 and FR-2 galaxies. Their higher number density makes them interesting candidate sources for an isotropic contribution to the observed UHECR flux. Here, acceleration and survival of UHECR in prevailing conditions of the FR-0 environment are...

388. 【337】Increasing the ionization yield for the detection of 236U and 233U by AMS

Michael Kern (University of Vienna, Faculty of Physics - Isotope Physics)

01/09/2021, 18:30

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The detection efficiency of Accelerator Mass Spectrometry for long lived uranium isotopes (${}^{236}$U or ${}^{233}$U) is mainly limited by the rather low yield of the corresponding negative ions extracted from a caesium sputter ion source (≈ 10${}^{–4}$). With our new sample preparation method environmental U is embedded in only 200 µg Fe${}_2$O${}_3$ matrix which is then mixed with PbF${}_2$. Extracting...

34. 【357】Multi-messenger characterization of Mrk501 during historically low X-ray and gamma-ray activity

Lea Alina Heckmann (Max Planck Institute for Physics)

01/09/2021, 18:30

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

In this contribution, we describe the multi-wavelength behavior of Mrk501 from 2017 to 2020, when a very low VHE flux was observed. Alongside the monitoring campaign, three NuSTAR observations were conducted displaying three different low-activity flux levels. This dataset enables us to study multi-wavelength variability and correlations in detail, and allows to identify a historically low...

392. 【338】Determination of 135Cs and 137Cs by Accelerator Mass Spectrometry

Alexander Wieser (University of Vienna)

01/09/2021, 18:45

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The radionuclides ¹³⁵Cs and ¹³⁷Cs are present in the environment with an isotopic ratio ^135,137Cs/Cs ranging below 10^-10. The isotopic ratio ¹³⁵Cs/¹³⁷Cs can be used for source assessment of anthropogenic cesium input into the environment and finds applications in geology, nuclear forensics and oceanography. The combination of...

384. 【339】AMS of 90Sr at the sub-fg-level using laser photodetachment at VERA

Oscar Marchhart (University of Vienna, Faculty of Physics - Isotope Physics)

01/09/2021, 19:00

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

${}^{90}$Sr is among the most hazardous fission products with a high production yield in the nuclear fuel cycle and is of great environmental interest due to its radiotoxicity as well as its potential as a tracer. Accelerator Mass Spectrometry (AMS) is the technique of choice for the detection of minute environmental levels of long-lived radionuclides, but the background from the abundant stable...

15. 【362】Ultracold neutron production and extraction from the solid deuterium moderator of the PSI UCN source

Ingo Rienäcker (PSI - Paul Scherrer Institut)

02/09/2021, 14:30

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

Ultracold neutrons (UCN) with kinetic energies below 300 neV can be confined for hundreds of seconds, making them ideal for experiments that benefit from long observation times. One of these experiments at the Paul Scherrer Institute (PSI) searches for the CP violating permanent neutron electric dipole moment, probing beyond Standard Model physics. Such precision experiments with UCN are...

144. 【381】Completing the data transmission chain for the HL-LHC ATLAS ITk Pixel detector

Thierry Guillaume Harte (Universitaet Bern (CH))

02/09/2021, 14:30

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

In preparation for the High-Luminosity upgrade of the Large Hadron Collider, the ATLAS detector will be upgraded in 2025-2027. Its new Inner Tracker (ITk) Pixel detector is designed to cope with 200 interactions per bunch crossing, which produces a digital output of up to 11Tb/s. A new data transmission chain, able to transmit such a high data rate in the high-radiation environment has been...

92. 【363】Muonic atom spectroscopy with radioactive targets

Stergiani Marina Vogiatzi (PSI - Paul Scherrer Institut)

02/09/2021, 14:45

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

An experiment at PSI, carried out by the muX collaboration, aims to measure the nuclear charge radii of radioactive elements such as ${}^{226}\mathrm{Ra}$ and ${}^{248}\mathrm{Cm}$ with muonic atoms. An intermediate test performed with ${}^{185,187}\mathrm{Re}$ targets in 2016 led to the extraction of their spectroscopic quadrupole moments. Typical muonic spectroscopy experiments require targets of...

147. 【382】Silicon strip sensors for the CMS Tracker Phase-2 Upgrade

Konstantinos Damanakis (Austrian Academy of Sciences (AT))

02/09/2021, 14:45

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The operation of the LHC beyond 2026, which aims to reach luminosities around 5-7.5 x 1034 cm-2s-1 , poses new challenges for the CMS detector. Therefore, the Phase-2 upgrade of CMS will completely replace the tracking system including more advanced silicon sensors/electronics which can sustain higher radiation levels and ensure efficient tracking performance. Studying and testing the...

129. 【364】High Intensity Muon Beam project (HIMB): how to improve the most intense muon beam in the world

Giovanni Dal Maso (PSI - Paul Scherrer Institut)

02/09/2021, 15:00

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

Currently PSI delivers the most intense continuous muon beam in the world with up to few 10^8 μ+/s. The High Intensity Muon Beam (HiMB) project aims at developing a new target station and muon beam lines able to deliver up to 10^10 μ+/s, with a huge impact for low-energy, high-precision muon based searches.

To do so, the focus is on two key points: increasing the surface muon production...

151. 【383】Silicon sensor development for the High Granularity Calorimeter of the CMS experiment at CERN

Maximilian Babeluk (Austrian Academy of Sciences (AT))

02/09/2021, 15:00

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The CMS phase-2 upgrade, necessary to cope with the radiation levels and pileup of the High-Luminosity LHC, requires a finer granularity, radiation-tolerant endcap calorimeter. This is achieved by 600 m^2 of silicon sensors as detector material for the highly radiated regions, together with scintillator tiles with individual SiPM readout. To reduce the cost, a new 8-inch wafer process is used,...

140. 【365】A final cooling scheme for muon colliders: a door opener for future discovery machines

Bernd Michael Stechauner (Vienna University of Technology (AT))

02/09/2021, 15:15

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

Due to negligible synchrotron radiation, muon colliders have been considered a promising tool for new discoveries. A hot hadronic shower serves as a muon source. However, the large emittance of the produced beams poses a critical challenge for the design of muon colliders which require high-charge and dense muon beams. The only feasible way to reduce this emittance within the muons’ short...

167. 【384】The upgrade of the CMS Electromagnetic Calorimeter for the High-Luminosity LHC

Luigi Marchese (ETH Zurich (CH))

02/09/2021, 15:15

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The Electromagnetic Calorimeter (ECAL) of the CMS experiment at CERN is a hermetic, fine grained, homogeneous calorimeter made of about 75,848 lead tungstate scintillating crystals. During the Run 1 and Run 2 operations of the Large Hadron Collider of CERN, the CMS ECAL played a key role in the discovery of the Standard Model Higgs Boson. In order to cope with ∼140 pileup events expected for...

171. 【366】Development of a high-brightness ultra-cold muon beam for future precision experiments with muons and muonium

Ryoto Iwai (ETH Zurich)

02/09/2021, 15:30

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The Paul Scherrer Institute (PSI) provides the world's highest intensity DC muon beam of $\mathcal{O}({10}^8){\mu }^{+}/$s at 28$$MeV/c. The muCool collaboration is developing a device which converts such a beam of cm-size and MeV-energy into a low-energy beam of sub-mm size and 1$$eV energy spread by achieving a compression of the 6-dimensional phase space by 10 orders of magnitude with a...

236. 【385】Micro-lens enhanced silicon photomultiplier arrays for the LHCb SciFi Tracker

Carina Trippl (EPFL - Ecole Polytechnique Federale Lausanne (CH))

02/09/2021, 15:30

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

A new scintillating-fibre (SciFi) tracker is being installed and commissioned as part of the ongoing LHCb upgrade. As a consequence of the radiation the over-all light yield of the detector will be reduced in the course of LHC Run 3, compromising the hit detection efficiency. The inner modules will thus be replaced during the next long shutdown (2025–2027). For this occasion, a development of...

241. 【367】Muonium Spectroscopy

Irene Cortinovis (ETH Zurich (CH))

02/09/2021, 15:45

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

I will introduce here the MuMASS experiment, aiming to improve the current results on the Muonium Lamb Shift and the 1S-2S frequency measurements by orders of magnitude. I will present our most recent results of the Lamb Shift determination, which could already set competitive limits on New Physics, in particular on possible CPT and Lorentz violations. I will conclude with the current state of...

273. 【386】The SND@LHC data acquisition system

Ettore Zaffaroni (EPFL - Ecole Polytechnique Federale Lausanne (CH))

02/09/2021, 15:45

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The SND@LHC (Scattering and Neutrino Detector at the LHC) is a recently approved neutrino and feebly interacting particles search experiment, based at CERN.
It is located 480 m away from the ATLAS interaction point and consists of a target region built of emulsion-tungsten walls interleaved by scintillating fibre planes, a hadronic calorimeter built of scintillating bars and iron absorbers,...

279. 【368】Investigation of muonium emitters at room temperature

Jonas Nuber (PSI - Paul Scherrer Institut)

02/09/2021, 16:00

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

Muonium (M) atoms are interesting for a diverse palette of experiments reaching from precision spectroscopy to muon beam cooling and anti-matter gravity. We have been investigating new M emitters at room temperature. For the room-temperature study we have developed three compact experimental setups in order to compare vacuum yields and dynamic properties of various emitters. The setups pursue...

298. 【387】Powering the opto-electrical conversion system for the data transmission of the ATLAS Inner Tracker detector at the HL-LHC

Jan Andreas Kunzmann (Universitaet Bern (CH))

02/09/2021, 16:00

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

In view of the High Luminosity phase of the Large Hadron Collider the ATLAS experiment will upgrade its Inner Detector replacing it with an full-silicon Inner Tracker (ITk). The modules of this pixel detector will output data at a high data rate, each module producing up to 5.12 Gb/s. The ITk Pixel data transmission chain features an opto-electrical conversion system (Optosystem) powered by a...

367. 【388】CMS Phase-1 pixel detector readiness for the next LHC Run

Lars Noehte (Universitaet Zuerich (CH))

02/09/2021, 16:15

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The CMS Phase-1 pixel detector has been operated successfully during the course of the LHC Run 2, ended in 2018. In order to allow to maintain the excellent performance during Run 3 (starting in 2022), the innermost barrel layer has been replaced with new modules, assembled and tested at PSI during the LHC shutdown.

This contribution provides an overview of the CMS Phase-1 pixel...

305. 【371】Exploring coherent neutrino-nucleus scattering with NUCLEUS experiment

Dr Vasile Mihai Ghete (Austrian Academy of Sciences (AT))

02/09/2021, 17:00

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The NUCLEUS experiments aims to perform a high-precision measurement of the coherent elastic neutrino–nucleus scattering (CEvNS) at the EdF Chooz B nuclear power plant in France.
CEvNS is a unique process to study neutrino properties and to search for new physics beyond the Standard Model. NUCLEUS is based on cryogenic detectors, operated at temperature of the order of 10 mK, with...

326. 【391】Measurement of the Higgs boson production in the associated vector boson production mode where the vector boson decays leptonically and the Higgs boson decays to a pair of bottom quarks

Krunal Bipin Gedia (ETH Zurich (CH))

02/09/2021, 17:00

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

In 2012, the ATLAS and CMS Collaborations announced the discovery of a new state with a mass around 125 GeV, compatible with the Standard Model Higgs boson.

In 2018, the Higgs boson to bottom quark coupling was observed with a significance of 5.6 sigma using the full Run 1+2016+2017 data by the CMS collaboration.

Further precision measurements of the Higgs boson coupling to bottom quark...

138. 【372】Latest results of NA64 searching for Dark Sectors at the CERN SPS

Benjamin Banto Oberhauser (ETH Zurich (CH))

02/09/2021, 17:15

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

NA64 is a high-intensity frontier experiment running at the CERN SPS. NA64 searches for possible candidates of mediators between the dark sector and the standard model by looking for missing energy events in an active beam dump. I will present the latest results of NA64 running in electron mode setting constraints in the mass-coupling parameter space for the vector and the axion portals to the...

70. 【392】Measurement of the inclusive and differential $t\overline{t}\gamma$ cross sections and EFT interpretation in the single-lepton channel at CMS

Lukas Lechner (Austrian Academy of Sciences (AT))

02/09/2021, 17:15

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The $t\overline{t}\gamma$ cross-section is measured at a center-of-mass energy of $13\text{TeV}$, using a data-set corresponding to an integrated luminosity of $137{\text{fb}}^{-1}$, recorded by the CMS experiment. Events with an isolated, highly energetic lepton, at least three jets from the hadronization of quarks, among which at least one is b-tagged, and with one isolated photon are selected....

204. 【373】Searches for Dark Sectors Weakly Coupled to Muons at the NA64$\mu$ experiment at CERN

Henri Hugo Sieber (ETH Zurich (CH))

02/09/2021, 17:30

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

NA64$\mu$ aims at searching for light dark sector particles weakly coupled to muons at the CERN SPS. These searches are sensitive to dark photons in a mass region larger than 0.1 GeV, which is not accessible with NA64e. The combination of both experiments will allow to completely explore the very interesting thermal light dark matter parameter space. NA64$\mu$ will be also sensitive to $Z^{\prime }$...

117. 【393】EFT measurements using top quarks with CMS

Dennis Schwarz (Austrian Academy of Sciences (AT))

02/09/2021, 17:30

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

Resonant production of physics beyond the standard model can be probed up to the TeV scale by the experiments at the LHC. Until now, no indication of new physics was found at these high energies. Complementary to direct searches, indirect effects of new physics at even higher energy scales can be studied in the model independent framework of effective field theories(EFTs).

Due to its mass,...

110. 【374】Sp(4) SIMP Dark Matter on the Lattice

Fabian Zierler (University of Graz)

02/09/2021, 17:45

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The Strongly Interacting Massive Particle (SIMP) paradigm provides dark matter (DM) candidates as pseudo-Goldstone bound states of dark fermions under a new gauge group. Freeze-out then occurs through $3\to 2$ dark matter self-annihilation and points to DM masses of $O(100\text{MeV})$. We study the spectrum of the lightest mesons of $Sp(4)$ gauge theory with $2$ fundamental Dirac fermions...

69. 【394】SMEFT results in Higgs sector from CMS experiment

Suman Chatterjee (Austrian Academy of Sciences (AT))

02/09/2021, 17:45

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

A generalized extension of the standard model of particle physics (SM), known as standard model effective field theory (SMEFT), consists of all the possible operators of dimensions greater than four, satisfying the symmetries of the SM Lagrangian. SMEFT operators, which systematically parameterize the impact of physics beyond the SM in a model-independent way, modify the production and decay...

336. 【375】ArDM - The only Dual-Phase Tonne-scale Liquid Argon Dark Matter Detector

Alexander Martin Stauffer (ETH Zurich (CH))

02/09/2021, 18:00

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

ArDM is the only dual-phase tonne-scale liquid Argon Dark Matter detector for the direct search of Weakly Interacting Massive Particles (WIMPs). The scintillation light and ionization charge produced by recoiling nuclei in WIMP‐Argon collisions can be measured independently. The WIMP/neutron-induced nuclear recoils can be discriminated from the electron/photon background via the pulse shape of...

399. 【395】Top mass calibration for Monte-Carlo event generators

Oliver Jin (University of Vienna)

02/09/2021, 18:00

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The relation between the top quark mass parameters of Monte-Carlo event generators and renormalized and well-defined Lagrangian masses is not very well understood and a subject of intense discussions in the community given that the current experimental uncertainties in direct top mass determinations is at the level of 300 MeV.
In this presentation I talk about preliminary results where the...

265. 【376】Measurement of the Lamb shift of Antihydrogen atoms in GBAR

Philipp Peter Blumer (ETH Zurich (CH))

02/09/2021, 18:15

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

This Fall the upgrade of the antiproton decelerator, the Extra Low ENergy Antiproton (ELENA) ring, will start operation at CERN opening a new era for antihydrogen research. In the context of the GBAR experiment aiming to study the gravitational behaviour of antimatter, our group from ETHZ proposed and is preparing a Lamb shift measurement of antihydrogen with an uncertainty of...

328. 【396】zfit: scalable pythonic fitting

Jonas Eschle (Universitaet Zuerich (CH))

02/09/2021, 18:15

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

Statistical modelling is a key element in many parts of physics, especially in High-Energy Physics (HEP). zfit is a Python library for unbinned, likelihood model fitting. Its main computational backend is TensorFlow, an easy-to-use, highly scalable computing library similar to Numpy. zfit provides a high level interface for advanced model building and fitting while also designed with a unified...

127. 【377】Black Holes, Entropy and Holography

Raphaela Wutte (TU Wien)

02/09/2021, 18:30

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

Black Holes are one of the most interesting consequences of Einstein's general relativity. Since their theoretical prediction they have engendered a lot of research, both theoretically and experimentally. However, to this day, many aspects of black holes are not sufficiently well understood. One such aspect is the origin of their huge gravitational entropy. In this talk, I will explain how the...

402. 【397】Towards Colour Flow Evolution at Two loops

Ines Ruffa (University of Vienna)

02/09/2021, 18:30

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

In the presentation I intend to give an overview of the one-loop/one-emission and two-loop contributions required for soft gluon evolution and the resummation of non-global logarithms at the next logarithmic order. I will present the general structure of the soft anomalous dimension matrix in the colour-flow basis and highlight the importance of three-parton correlations which appear at...

322. 【378】Novel Developments in R-Matrix Theory

Prof. Helmut Leeb (Vienna University of Technology (AT))

02/09/2021, 18:45

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

At present R-matrix analyses are widely performed in order to obtain a good representation of the experimental data, especially for light nuclear systems. A versatile R-matrix code with several non-standard capabilities was developed and successfully applied to experimental data. However, the standard R-matrix method can only be applied for binary reactions. Breakup channels, which may occur...

134. 【398】Generalization abilities of translationally equivariant neural networks

Daniel Schuh (Vienna University of Technology)

02/09/2021, 18:45

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

Machine learning has become increasingly popular in physics over the last decade. Recently, big efforts have been made to incorporate global and gauge symmetries in different neural network architectures. In this talk, I will focus on translational symmetry, which is an important idea behind Convolutional Neural Networks (CNNs). After explaining possible ways to ensure translational...

5. Testing the Strong Interaction at Low Energies with the SIDDHARTA-2 Apparatus

Marlene Tuechler (Stefan Meyer Institute)

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

Kaonic atoms provide an ideal probe to test the low-energy QCD. The SIDDHARTA-2 experiment aims to measure the 2p$\to$1s transition in kaonic deuterium to extract the energy shift and broadening of the K${}^{-}$d ground state, induced by the strong interaction. Due to the low K${}^{-}$d X-ray yield, the signal-to-background ratio has to be increased by one order of magnitude compared to...

199. 【320】Flat space holography

Daniel Grumiller (TU Wien)

Nuclear, Particle- and Astrophysics (FAKT - TASK)

Talk

The holographic principle posits that quantum gravity in D dimensions is equivalent to quantum field theory in one lower dimension. Almost a quarter of a century ago, it has been implemented successfully within string theory in the context of the AdS/CFT correspondence, which requires spacetime to be negatively curved. An outstanding question is the generality of holography, and in particular...