Tue·Nov 8, 2022Tuesday·November 8, 2022

1. 01*

   Isoscaling in central Sn+Sn collisions at 270 MeV/u

   J.W. Lee (1)🇰🇷 · M.B. Tsang (2 and 3)🇺🇸 · C.Y. Tsang (2 and 3)🇺🇸 · R. Wang (2)🇺🇸 · J. Barney (2 and 3)🇺🇸 · J. Estee (2 and 3)🇺🇸 · T. Isobe (4)🇯🇵 · M. Kaneko (4 and 5)🇯🇵 · M. Kurata-Nishimura (4)🇯🇵 · W.G. Lynch (2 and 3)🇺🇸 · T. Murakami (e6 and 4 and 5)🇯🇵 · A. Ono (6)🇯🇵 and 52 other authors

   Experimental information on fragment emissions is important in understanding the dynamics of nuclear collisions and in the development of transport model simulating heavy-ion collisions. The composition of complex fragments emitted in the heavy-ion collisions can be explained by statistical models, which assume that thermal equilibrium is achieved at collision energies below 100 MeV/u. Our new experimental data together with theoretical analyses for light particles from Sn+Sn collisions at 270 MeV/u, suggest that the hypothesis of thermal equilibrium breaks down for particles emitted with high transfer momentum. To inspect the system's properties in such limit, the scaling features of the yield ratios of particles from two systems, a neutron-rich system of ${}^{132}\mathrm{Sn}+{}^{124}\mathrm{Sn}$ and a nearly symmetric system of ${}^{108}\mathrm{Sn}+{}^{112}\mathrm{Sn}$, are examined in the framework of the statistical multifragmentation model and the antisymmetrized molecular dynamics model. The isoscaling from low energy particles agree with both models. However the observed breakdown of isoscaling for particles with high transverse momentum cannot be explained by the antisymmetrized molecular dynamics model.

   nucl-exnucl-thEPJA(2022)·15 citations
2. 02*

   Observation of a nuclear recoil peak at the 100 eV scale induced by neutron capture

   CRAB Collaboration · NUCLEUS Collaboration: H. Abele (1) · G. Angloher (2) · A. Bento (2 and 3) · L. Canonica (2) · F. Cappella (4) · L. Cardani (4) · N. Casali (4) · R. Cerulli (5 and 6) · A. Chalil (7) · A. Chebboubi (8) · I. Colantoni (4 and 9) and 65 other authors

   Coherent elastic neutrino-nucleus scattering and low-mass Dark Matter detectors rely crucially on the understanding of their response to nuclear recoils. We report the first observation of a nuclear recoil peak at around 112 eV induced by neutron capture. The measurement was performed with a CaWO${}_4$ cryogenic detector from the NUCLEUS experiment exposed to a ${}^{252}$Cf source placed in a compact moderator. The measured spectrum is found in agreement with simulations and the expected peak structure from the single-$\gamma$ de-excitation of ${}^{183}$W is identified with 3 $\sigma$ significance. This result demonstrates a new method for precise, in-situ, and non-intrusive calibration of low-threshold experiments.

   nucl-exphysics.ins-detPRL(2023)·41 citations
3. 03*

   Charm and beauty production and hadronization with the ALICE experiment

   Robert Vertesi (for the ALICE Collaboration)🇭🇺

   This contribution summarizes a selection of recent results from the ALICE experiment. We show the cross-section of beauty jets in pp collisions, as well as the charmed baryon-to-meson production ratios, down to unprecedentedly low momenta, at $\sqrt{s_{\mathrm{NN}}}=5.02$ and 13 TeV collision energies. We present the nuclear modification of ${\mathrm{D}}^0$-jets and the $v_2$ of non-prompt ${\mathrm{D}}^0$ in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV. We also discuss the implications and constraints from comparing these data to some of the most recent theoretical models.

   nucl-exhep-exActa Phys.Polon.Supp.(2023)·0 citations
4. 04*

   The Electron-Ion Collider -- A U.S. facility for the European community to explore the mysteries of the building blocks of matter

   Marco Radici🇮🇹 · Silvia Dalla Torre🇮🇹 · Daria Sokhan🇫🇷

   This document is submitted as input to the NuPECC Long Range Plan 2024 by three European members of the EIC Users Group Steering Committee (Vice Chair, one at-large member, and the EU Representative). We submit the document on behalf of the international EIC Users Group (EICUG) community, but we specifically represent 335 European members of the EICUG (25%) based in 80 institutions (30% of the total) located in Armenia, Czech Republic, Finland, France, Germany, Hungary, Ireland, Israel, Italy, Netherlands, Norway, Poland, Slovenia, Spain, Sweden, Switzerland, Ukraine, and the United Kingdom. This European involvement is an important driver of the EIC, but can also be beneficial for a number of related ongoing and planned nuclear physics experiments in Europe. In this document, the shared interest regarding scientific questions and detector R&D between the EIC and European nuclear physics communities is outlined. The aim is to highlight how these synergies offer ample opportunities to foster progress at the forefront of nuclear physics.

   ↳ hep-phhep-exnucl-exnucl-th1 citation
5. 05*

   Optimization of generator coordinate method with machine-learning techniques for nuclear spectra and neutrinoless double-beta decay: ridge regression for nuclei with axial deformation

   X. Zhang🇨🇳 · W. Lin🇨🇳 · J. M. Yao🇨🇳 · C. F. Jiao🇨🇳 · A. M. Romero🇺🇸 · T. R. Rodríguez🇪🇸 · H. Hergert🇺🇸

   The generator coordinate method (GCM) is an important tool of choice for modeling large-amplitude collective motion in atomic nuclei. The computational complexity of the GCM increases rapidly with the number of collective coordinates. It imposes a strong restriction on the applicability of the method. In this work, we propose a subspace-reduction algorithm that employs optimal statistical ML models as surrogates for exact quantum-number projection calculations for norm and Hamiltonian kernels. The model space of the original GCM is reduced to a subspace relevant for nuclear low energy spectra and the NME of ground state to ground state $0\nu \beta \beta$ decay based on the orthogonality condition (OC) and the energy-transition-orthogonality procedure (ENTROP), respectively. For simplicity, the polynomial ridge regression (RR) algorithm is used to learn the norm and Hamiltonian kernels of axially deformed configurations. The efficiency and accuracy of this algorithm are illustrated for 76Ge and 76Se by comparing results obtained using the optimal RR models to direct GCM calculations. The low-lying energy spectra of ${}^{76}$Ge and ${}^{76}$Se, as well as the $0\nu \beta \beta$-decay NME between their ground states, are computed. The results show that the performance of the GCM+OC/ENTROP+RR is more robust than that of the GCM+RR alone, and the former can reproduce the results of the original GCM calculation accurately with a significantly reduced computational cost.

   ↳ nucl-thnucl-exPRC(2023)·11 citations
6. 06*

   Status and performance of the AMoRE-I experiment on neutrinoless double beta decay

   H.B. Kim🇰🇷 · D.H. Ha🇰🇷 · E.J. Jeon🇰🇷 · J.A. Jeon🇰🇷 · H.S. Jo🇰🇷 · C.S. Kang🇰🇷 · W.G. Kang🇰🇷 · H.S. Kim🇰🇷 · S.C. Kim🇰🇷 · S.G. Kim🇰🇷 · S.K. Kim🇰🇷 · S.R. Kim🇰🇷 and 23 other authors

   AMoRE is an international project to search for the neutrinoless double beta decay of ${}^{100}$Mo using a detection technology consisting of magnetic microcalorimeters (MMCs) and molybdenum-based scintillating crystals. Data collection has begun for the current AMORE-I phase of the project, an upgrade from the previous pilot phase. AMoRE-I employs thirteen ${}^{48depl.}$Ca${}^{100}$MoO${}_4$ crystals and five Li${}_2$${}^{100}$MoO${}_4$ crystals for a total crystal mass of 6.2 kg. Each detector module contains a scintillating crystal with two MMC channels for heat and light detection. We report the present status of the experiment and the performance of the detector modules.

   ↳ physics.ins-dethep-exnucl-exJ.Low Temp.Phys.(2022)·32 citations
7. 07*

   Revealing the Signal of QCD Phase Transition in Heavy-Ion Collisions

   Yi Lu🇨🇳 · Fei Gao🇨🇳 · Xiaofeng Luo🇨🇳 · Lei Chang🇨🇳 · Yu-xin Liu🇨🇳

   We propose a novel method to construct the Landau thermodynamic potential directly from the fluctuations measured in heavy-ion collisions. The potential is capable of revealing the signal of the critical end-point (CEP) and the first order phase transition (FOPT) of QCD in the system even away from the phase transition region. With the available experimental data, we show that the criterion of the FOPT is negative for most of the collision energies which indicates no signal of FOPT. The data at $\sqrt{s_{\mathrm{NN}}}=7.7$ GeV with 0-5% centrality shows a different behavior and the mean value of the data satisfies the criterion. However, the uncertainty is still too large to make a certain conclusion. The higher order fluctuations are also required for confirming the signal. We emphasize therefore that new measurements with higher precision for the $C_{1,...,6}$ within 0-5% centrality in the vicinity of $\sqrt{s_{\mathrm{NN}}}=7.7$ GeV are in demand which may finally reveal the signal of QCD phase transition.

   ↳ hep-phnucl-exnucl-th1 citation
8. 08*

   Modelling of transient interference phenomena in collinear laser spectroscopy

   Jovan Jovanovic · Ronald Fernando Garcia Ruiz🇺🇸

   Collinear laser spectroscopy of fast atomic beams has been established as one of the main tools to perform precision experiments with atoms containing short-lived nuclei. Although highly sensitive, the spectral resolution of these techniques is typically limited to several MHz. Here, we study the use of transient interference phenomena to potentially improve the experimental resolution. Previous attempts to implement Ramsey-type measurements with fast beams were limited by the lack of understanding of the observed line shapes. By using a simple model, we provide a satisfactory description of the previously observed line shapes, and propose alternative experimental schemes to improve the resolution in fast ion-beam experiments.

   ↳ physics.atom-phnucl-exPRA(2023)·1 citation
9. 09*

   First Measurement of Differential Cross Sections for Muon Neutrino Charged Current Interactions on Argon with a Two-proton Final State in the MicroBooNE Detector

   MicroBooNE collaboration: P. Abratenko · D. Andrade Aldana · L. Arellano · J. Asaadi · A. Ashkenazi · S. Balasubramanian · B. Baller · A. Barnard · G. Barr · D. Barrow · J. Barrow · V. Basque and 189 other authors

   We present the first measurement of differential cross sections for charged-current muon neutrino interactions on argon with one muon, two protons, and no pions in the final state. These final states are dominated by two-nucleon knockout interactions, which are complicated to model and for which there is currently limited information about the characteristics of these interactions in existing neutrino-nucleus scattering data. Detailed investigations of two-nucleon knockout are vital to support upcoming experiments exploring the nature of the neutrino. Among the different kinematic quantities measured, the opening angle between the two protons, the angle between the total proton momentum and the muon, and the total transverse momentum of the final state system are most sensitive to the underlying physics processes as embodied in various theoretical models.

   ↳ hep-exnucl-exPLB(2026)·21 citations
10. 10*

    Two-neutrino $\beta \beta$ decay of ${}^{136}$Xe to the first excited $0^{+}$ state in ${}^{136}$Ba

    Lotta Jokiniemi🇨🇦 · Beatriz Romeo🇪🇸 · Catharina Brase🇩🇪 · Jenni Kotila🇫🇮 · Pablo Soriano🇪🇸 · Achim Schwenk🇩🇪 · Javier Menéndez🇪🇸

    We calculate the nuclear matrix element for the two-neutrino $\beta \beta$ decay of ${}^{136}$Xe into the first excited $0^{+}$ state of ${}^{136}$Ba. We use different many-body methods: the quasiparticle random-phase approximation (QRPA) framework, the nuclear shell model, the interacting boson model (IBM-2), and an effective field theory (EFT) for $\beta$ and $\beta \beta$ decays. While the QRPA suggests a decay rate at the edge of current experimental limits, the shell model points to a half-life about two orders of magnitude longer. The predictions of the IBM-2 and the EFT lie in between, and the latter provides systematic uncertainties at leading order. An analysis of the running sum of the nuclear matrix element indicates that subtle cancellations between the contributions of intermediate states can explain the different theoretical predictions. For the EFT, we also present results for two-neutrino $\beta \beta$ decays to the first excited $0^{+}$ state in other nuclei.

    ↳ nucl-thhep-exhep-phnucl-exPLB(2023)·15 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.