Tue·Jul 15, 2025Tuesday·July 15, 2025

1. 01*

   Measurements of $D^0$ and $D^{\ast }$ production in p+p collisions at $\sqrt{s}$ = 510 GeV in STAR experiment

   Subhadip Pal (for the STAR Collaboration)🇨🇿

   These proceedings present an investigation into the production of $D^0$ and $D^{\ast }$ mesons as a function of transverse momentum in proton-proton (p+p) collisions at a center-of-mass energy of $\sqrt{s}$ = 510 GeV, in the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). Objective of this analysis is to test the perturbative QCD calculations with the charm-anticharm production cross-sections obtained through $D^0$ and $D^{\ast }$ measurements. This report includes ongoing signal extractions of the $D^0$ and $D^{\ast }$ mesons from minimum bias events recorded during the p+p collisions at $\sqrt{s}$ = 510 GeV at STAR in 2017. Signals were reconstructed through the hadronic decay channels of these mesons. Like-sign combination and track rotation methods have been used to estimate the combinatorial background for $D^0$ measurement from $p_T$ = 0.0 to 2.1 GeV/$c$. For $D^{\ast }$, wrong-sign and side band combination of the decay daughters were utilized to reconstruct the combinatorial background from $p_T$ = 2.0 to 6.0 GeV/$c$.

   nucl-ex0 citations
2. 02*

   Phenomenological Modeling of the ${}^{163}$Ho Calorimetric Electron Capture Spectrum from the HOLMES Experiment

   F. Ahrens🇮🇹 · B. K. Alpert🇺🇸 · D. T. Becker🇺🇸 · D. A. Bennett🇺🇸 · E. Bogoni🇮🇹 · M. Borghesi🇮🇹 · P. Campana🇮🇹 · R. Carobene🇮🇹 · A. Cattaneo🇮🇹 · A. Cian🇮🇹 · H. A. Corti🇮🇹 · N. Crescini🇮🇹 and 37 other authors

   We present a comprehensive phenomenological analysis of the calorimetric electron capture (EC) decay spectrum of ${}^{163}$Ho as measured by the HOLMES experiment. Using high-statistics data, we unfold the instrumental energy resolution from the measured spectrum and model it as a sum of Breit-Wigner resonances and shake-off continua, providing a complete set of parameters for each component. Our approach enables the identification and tentative interpretation of all observed spectral features, including weak and overlapping structures, in terms of atomic de-excitation processes. We compare our phenomenological model with recent ab initio theoretical calculations, finding good agreement for both the main peaks and the spectral tails, despite the limitations of current theoretical and experimental precision. The model delivers an accurate description of the endpoint region, which is crucial for neutrino mass determination, and allows for a realistic treatment of backgrounds such as pile-up and tails of low-energy components. Furthermore, our decomposition facilitates the generation of Monte Carlo toy spectra for sensitivity studies and provides a framework for investigating systematic uncertainties related to solid-state and detector effects. This work establishes a robust foundation for future calorimetric neutrino mass experiments employing ${}^{163}$Ho, supporting both data analysis and experimental design.

   nucl-exhep-phphysics.ins-detJHEP(2026)·4 citations
3. 03*

   Evidence of medium response to hard probes using correlations of Z bosons with hadrons in heavy ion collisions

   CMS Collaboration

   The first measurement of pseudorapidity and azimuthal angle distributions relative to the momentum vector of a Z boson for low transverse momentum ($p_{\mathrm{T}}$) charged hadrons in lead-lead (PbPb) collisions is presented. By studying the hadrons produced in an event with a high-$p_{\mathrm{T}}$ Z boson (40 $<$ $p_{\mathrm{T}}$ $<$ 350 GeV), the analysis probes how the quark-gluon plasma (QGP) medium created in these collisions affects the parton recoiling opposite to the Z boson. Utilizing PbPb data at a nucleon-nucleon center-of-mass energy $\sqrt{s_{{}_{\mathrm{NN}}}}$ = 5.02 TeV from 2018 with an integrated luminosity of 1.67 nb${}^{-1}$ and proton-proton (pp) data at the same energy from 2017 with 301 pb${}^{-1}$, the distributions are examined in bins of charged-hadron $p_{\mathrm{T}}$. A significant modification of the distributions for charged hadrons in the range 1 $<$ $p_{\mathrm{T}}$ $<$ 2 GeV in PbPb collisions is observed when compared to reference measurements from pp collisions. The data provide new information about the correlation between hard and soft particles in heavy ion collisions, which can be used to test predictions of various jet quenching models. When compared to theoretical predictions, the results are consistent with expectations of a hydrodynamic wake created when the QGP is depleted of energy by the parton propagating through it. Therefore, this Letter presents the first evidence of probe-induced energy depletion and the resulting response by the QGP medium.

   nucl-exhep-exPLB(2026)·20 citations
4. 04*

   Theoretical evaluation of decay mode of ${}^{229m}\mathrm{Th}$ in solid samples

   Ryotaro Masuda🇯🇵 · Tomoya Naito🇯🇵 · Masashi Kaneko🇯🇵 · Hiroyuki Kazama · So Hashiba🇯🇵 · Kosuke Misawa · Yoshitaka Kasamatsu🇯🇵

   The excitation energy of ${}^{229m}\mathrm{Th}$ is extremely low at $8.4\mathrm{eV}$; thus, this isotope exhibits changes in its decay modes depending on the chemical state, specifically the outermost electronic states. However, the reported half-lives of the $\gamma$-ray transition are not consistent among the previous experiments. In this study, we investigate the chemical states of ${}^{229m}\mathrm{Th}$ by density functional theory calculations. Based on these results, we evaluate the relationship between the experimental half-life of each sample and the electronic state of $\mathrm{Th}$. The calculation results indicate that ion trap method, $\mathrm{Ca}{\mathrm{F}}_2$ model and $\mathrm{Mg}{\mathrm{F}}_2$ one decay only via the $\gamma$-ray transition, whereas $\mathrm{Li}\mathrm{Sr}\mathrm{Al}{\mathrm{F}}_6$ one decays via the $\gamma$-ray transition and has a possibility of decay via internal conversion and electron bridge.

   ↳ physics.atom-phcond-mat.othernucl-exnucl-th+1PRResearch(2025)·1 citation
5. 05*

   CycleGAN-Driven Transfer Learning for Electronics Response Emulation in High-Purity Germanium Detectors

   Kevin Bhimani🇺🇸 · Julieta Gruszko🇺🇸 · Morgan Clark🇺🇸 · John Wilkerson🇺🇸 · Aobo Li🇺🇸

   High-Purity Germanium (HPGe) detectors are a key technology for rare-event searches such as neutrinoless double-beta decay (\ensuremath{0\nu\beta\beta}) and dark matter experiments. Pulse shapes from these detectors vary with interaction topology and thus encode information critical for event classification. Pulse shape simulations (PSS) are essential for modeling analysis cuts that distinguish signal events from backgrounds and for generating reliable simulations of energy spectra. Traditional PSS methods rely on a series of first-principles corrections to replicate the effect of readout electronics, requiring challenging fits over large parameter spaces and often failing to accurately model the data. We present a neural network architecture, the Cyclic Positional U-Net (https://github.com/aobol/CPU-Net), that performs translations of simulated pulses so that they closely resemble measured detector signals. Using a Cycle Generative Adversarial Network (CycleGAN) framework, this {Response Emulation Network} (REN) learns a data-driven mapping between simulated and measured pulses with high fidelity, without requiring a predetermined response model. We use data from a High-Purity Germanium (HPGe) detector with an inverted-coaxial point contact (ICPC) geometry to show that \texttt{CPU-Net} effectively captures and reproduces critical pulse shape features, allowing more realistic simulations without detector-specific tuning. \texttt{CPU-Net} achieves up to a factor-of-four improvement in distribution-level agreement for pulse shape parameter reconstruction, while preserving the topology-dependent information required for pulse-shape discrimination.

   ↳ physics.ins-detnucl-exMach.Learn.Sci.Tech.(2026)·0 citations
6. 06*

   Proton radioactivity in deformed nuclei with microscopic optical potential: A novel angular-dependent emission mechanism in the nanosecond-lived ${}^{149}$Lu

   Yin Fan · Sibo Wang🇨🇳 · Xiao-Hua Li🇨🇳 · Haozhao Liang🇯🇵

   We present a theoretical description of proton radioactivity in 149Lu, the most oblate deformed proton emitter known, by combining a deformed microscopic optical potential derived from ab initio nuclear matter calculations with the Wentzel-Kramers-Brillouin penetration probabilities and the assault frequency of the emitted proton estimated through a new harmonic-oscillator-inspired scheme. We predict a novel angular-dependent phenomenon unprecedented in spherical proton emitters: the disappearance of classically allowed regions at small polar angles $(\theta \le 21^{\circ })$. Our framework yields a half-life $T_{1/2}=467_{-108}^{+143}$ ns for 149Lu, in excellent agreement within uncertainties with the experimental value $450_{-100}^{+170}$ ns. Deformation analysis rigorously excludes configurations with $|{\beta }_2|\ge 0.32$. Extensions to 150, 151Lu and their isomers also achieve excellent agreement with experimental half-life data. We further predict 148Lu as another highly oblate $({\beta }_2=-0.166)$ proton emitter with a half-life $T_{1/2}=4.42$ ns. This work validates deformed microscopic optical potentials as a robust predictive tool for drip-line proton emitters and provides quantitative evidence for deformation effects in exotic decays.

   ↳ nucl-thnucl-exPRC(2026)·2 citations
7. 07*

   Fragmentation of fully heavy tetraquarks: The TQ4Q1.1 functions as a case study

   Francesco Giovanni Celiberto🇪🇸

   We extend the study of exotic matter formation via the TQ4Q1.1 set of collinear, variable-flavor-number-scheme fragmentation functions for fully charmed or bottomed tetraquarks in three quantum configurations: scalar ($J^{PC}=0^{++}$), axial vector ($J^{PC}=1^{+-}$), and tensor ($J^{PC}=2^{++}$). We adopt single-parton fragmentation at leading power and implement a nonrelativistic Quantum Chromodynamics (NRQCD) factorization scheme tailored to tetraquark Fock-state configurations. Short-distance inputs at the initial scale are modeled using updated calculations for both gluon- and heavy-quark-initiated channels. A threshold-consistent Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) evolution is then applied via the novel Heavy-flavor nonrelativistic-evolution (HF-NRevo) hybrid scheme. We provide the first systematic treatment of uncertainties from nonperturbative color-composite long-distance matrix elements (LDMEs), as well as from perturbative hard-scattering (H-MHOUs) and fragmentation-scale inputs (F-MHOUs), assessed separately and in combination. To support phenomenology, we compute NLL/NLO${}^{+}$ cross sections for tetraquark-jet systems at the HL-LHC and FCC within the hybrid collinear and high-energy factorization (HyF) as implemented in (sym)JETHAD, incorporating angular multiplicities as key observables sensitive to high-energy QCD dynamics. We also provide expected event yields based on realistic luminosity scenarios, offering a concrete benchmark for experimental searches. This work connects the investigation of exotic hadrons with state-of-the-art precision QCD.

   ↳ hep-phhep-exnucl-exnucl-thPRD(2025)·23 citations
8. 08*

   Performance of newly constructed plastic scintillator barrel in the WASA-FRS experiments and evaluation of radiation damage effects on multi-pixel photon counter

   Y. K. Tanaka · R. Sekiya · K. Itahashi · H. Alibrahim Alfaki · F. Amjad · M. Armstrong · K.-H. Behr · J. Benlliure · Z. Brencic · T. Dickel · V. Drozd · S. Dubey and 61 other authors

   A barrel-shaped plastic scintillation counter with Multi-Pixel Photon Counter (MPPC) readout has been developed and operated in the first WASA-FRS experimental campaign at GSI. The detector was used to measure charged particles emitted from reactions induced by a 2.5 GeV proton beam incident on a carbon target, providing particle identification in combination with momentum reconstruction in a 1 T magnetic field. The performance of this detector, particularly its response to energy deposition and time resolution, was systematically investigated as a function of count rate and total number of irradiating protons. A time resolution of 45-75 ps ($\sigma$), depending on the energy deposition, was achieved. Stable performance was maintained under high-rate conditions up to 1.35 MHz per single counter, with no significant degradation in either signal amplitude or timing response. Radiation-induced damage to the MPPCs was observed primarily as a reduction in signal amplitude, with approximately $35\%$ decrease at an estimated 1 MeV neutron-equivalent fluence of $2.4\times 10^{10}$ cm${}^{-2}$.

   ↳ physics.ins-detnucl-exNucl.Instrum.Meth.A(2026)·1 citation

* 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.