Tue·Feb 20, 2024Tuesday·February 20, 2024

1. 01*

   Precision mass measurements in the zirconium region pin down the mass surface across the neutron midshell at $N=66$

   M. Hukkanen🇫🇮 · W. Ryssens🇧🇪 · P. Ascher🇫🇷 · M. Bender🇫🇷 · T. Eronen🇫🇮 · S. Grévy🇫🇷 · A. Kankainen🇫🇮 · M. Stryjczyk🇫🇮 · O. Beliuskina🇫🇮 · Z. Ge🇫🇮 · S. Geldhof🇧🇪 · M. Gerbaux🇫🇷 and 10 other authors

   Precision mass measurements of ${}^{104}$Y, ${}^{106}$Zr, ${}^{104,104m,109}$Nb, and ${}^{111,112}$Mo have been performed with the JYFLTRAP double Penning trap mass spectrometer at the Ion Guide Isotope Separator On-Line facility. The order of the long-lived states in ${}^{104}$Nb was unambiguously established. The trend in two-neutron separation energies around the $N=66$ neutron midshell appeared to be steeper with respect to the Atomic Mass Evaluation 2020 extrapolations for the ${}_{39}$Y and ${}_{40}$Zr isotopic chains and less steep for the ${}_{41}$Nb chain, indicating a possible gap opening around $Z=40$. The experimental results were compared to the BSkG2 model calculations performed with and without vibrational and rotational corrections. All of them predict two low-lying minima for ${}^{106}$Zr. While the unaltered BSkG2 model fails to predict the trend in two-neutron separation energies, selecting the more deformed minima in calculations and removing the vibrational correction, the calculations are more in line with experimental data. The same is also true for the $2_1^{+}$ excitation energies and differences in charge radii in the Zr isotopes. The results stress the importance of improved treatment of collective corrections in large-scale models and further development of beyond-mean-field techniques.

   nucl-exnucl-thPLB(2024)·16 citations
2. 02*

   Topological heavy-flavor tagging and intrinsic bottom at the Electron-Ion Collider

   Thomas Boettcher🇺🇸

   Heavy-flavor hadron production, in particular bottom hadron production, is difficult to study in deep-inelastic scattering (DIS) experiments due to small production rates and branching fractions. To overcome these limitations, a method for identifying heavy-flavor DIS events based on event topology is proposed. Based on a heavy-flavor jet tagging strategy developed for the LHCb experiment, this algorithm uses displaced vertices to identify decays of heavy-flavor hadrons. The algorithm's performance at the Electron-Ion Collider is demonstrated using simulation, and it is shown to provide discovery potential for non-perturbative intrinsic bottom quarks in the proton.

   ↳ hep-exhep-phnucl-exPRD(2024)·1 citation
3. 03*

   Bayesian uncertainty quantification on nuclear level density data and their impact on $(p,\gamma )$ reactions of astrophysical interest

   A. Chalil (1) · C. Ducoin (1) · O. Stézowski (1) · N. Millard-Pinard (1) · J. Dudouet (1) · Y. Demane (1) · M. Chamseddine (1) ((1) Univ. Lyon, Univ. Claude Bernard Lyon (1), (CNRS/IN2P3), (IP2I) Lyon, Villeurbanne, France)

   The $p$ process nucleosynthesis is responsible for the synthesis of 35 neutron-deficient nuclei from ${}^{35}$Se to ${}^{196}$Hg. An important input that can affect the modeling of this process is the nuclear level density at the relevant excitation energies of the nuclei involved in the reaction network. The OSLO method has been extensively used for the measurement of level densities in excitation energies of several MeV. In this work, Bayesian optimization has been used in order to estimate the 95% high density intervals for the parameters of two level density models optimized on the OSLO data. These uncertainties are then propagated on the cross sections of $(p,\gamma )$ reactions leading to the compound nuclei ${}^{105,106}$Pd and ${}^{105,106}$Cd inside the astrophysically relevant energy range. Imposing constraints in this region of the isotopic chart is important for network calculations involving the nearby $p$ nuclei ${}^{102}$Pd and ${}^{106}$Cd. We discuss the reduction of the range of cross sections due to the uncertainties arising from the level density data compared to the range of the six default level density models available in TALYS and we highlight the need for level density data inside the astrophysically relevant energy ranges.

   ↳ nucl-thnucl-exPRC(2024)·6 citations
4. 04*

   Nuclear matter radii from molecular rotations using ultra-high-resolution spectroscopy

   Michail Athanasakis-Kaklamanakis🇨🇭 · Gerda Neyens🇧🇪

   The rotational constant parametrizes the relative spacing between a molecule's rotational energy levels. It depends on the molecule's classical moments of inertia, which, in all studies, are expressed by treating the constituent nuclei as point masses separated by the bond length. We point out that treating the finite nuclear size leads to a correction to the rotational constant at the Hz level, which is resolvable with recently developed ultra-high-resolution molecular spectrometers. Nuclear-model-independent measurements of nuclear matter radii can thus be envisioned in the future using such apparatuses, advancing beyond the existing hadronic scattering experiments and further developing the intersection of nuclear and molecular physics. In the present time, it appears that the computational ability of ab initio quantum chemistry might be the limiting factor to the technical readiness of the approach. To test the premises of the proposed method, we call for benchmark experiments using HD+ that are feasible with state-of-the-art experiment and theory.

   ↳ physics.atom-phnucl-exPRResearch(2024)·1 citation
5. 05*

   BINGO innovative assembly for background reduction in bolometric $0\nu \beta \beta$ experiments

   A. Armatol · C. Augier · I.C. Bandac · D. Baudin · G. Benato · V. Berest · L. Bergé · J. Billard · J.M. Calvo-Mozota · P. Carniti · M. Chapellier · F.A. Danevich and 36 other authors

   BINGO is a project aiming to set the grounds for large-scale bolometric neutrinoless double-beta-decay experiments capable of investigating the effective Majorana neutrino mass at a few meV level. It focuses on developing innovative technologies (a detector assembly, cryogenic photodetectors and active veto) to achieve a very low background index, of the order of $10^{-5}$ counts/(keV kg yr) in the region of interest. The BINGO demonstrator, called MINI-BINGO, is designed to investigate the promising double-beta-decay isotopes ${}^{100}$Mo and ${}^{130}$Te and it will be composed of Li${}_2$MoO${}_4$ and TeO${}_2$ crystals coupled to bolometric light detectors and surrounded by a Bi${}_4$Ge${}_3$O${}_{12}$-based veto. This will allow us to reject a significant background in bolometers caused by surface contamination from $\alpha$-active radionuclides by means of light yield selection and to mitigate other sources of background, such as surface contamination from $\beta$-active radionuclides, external $\gamma$ radioactivity, and pile-up due to random coincidence of background events. This paper describes an R\&D program towards the BINGO goals, particularly focusing on the development of an innovative assembly designed to reduce the passive materials within the line of sight of the detectors, which is expected to be a dominant source of background in next-generation bolometric experiments. We present the performance of two prototype modules -- housing four cubic (4.5-cm side) Li${}_2$MoO${}_4$ crystals in total -- operated in the Canfranc underground laboratory in Spain within a facility developed for the CROSS double-beta-decay experiment.

   ↳ physics.ins-detnucl-exNucl.Instrum.Meth.A(2024)·8 citations
6. 06*

   4D Track Reconstruction on Free-Streaming Data at PANDA at FAIR

   Jenny Taylor🇸🇪 · Michael Papenbrock🇸🇪 · Tobias Stockmanns🇩🇪 · Ralf Kliemt🇩🇪 · Tord Johansson🇸🇪 · Adeel Akram🇸🇪 · Karin Schönning🇸🇪

   A new generation of experiments is being developed, where the challenge of separating rare signal processes from background at high intensities requires a change of trigger paradigm. At the future PANDA experiment at FAIR, hardware triggers will be abandoned and instead a purely software-based system will be used. This requires novel reconstruction methods with the ability to process data from many events simultaneously. A 4D tracking algorithm based on the cellular automaton has been developed which will utilize the timing information from detector signals. Simulation studies have been performed to test its performance on the foreseen free-streaming data from the PANDA detector. For this purpose, a quality assurance procedure for tracking on free-streaming data was implemented in the PANDA software. The studies show that at higher interaction rates, 4D tracking performs better than the 3D algorithm in terms of efficiency, 84% compared to 77%. The fake track suppression is also greatly improved, compared to the 3D tracking with roughly a 50% decrease in the ghost rate.

   ↳ physics.ins-detnucl-exComput.Softw.Big Sci.(2024)·0 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.