Tue·Jun 17, 2025Tuesday·June 17, 2025

1. 01*

   Studying Maximal Entanglement and Bell Nonlocality at an Electron-Ion Collider

   Wei Qi🇨🇳 · Zijing Guo🇨🇳 · Bo-Wen Xiao🇨🇳

   In this paper, we propose to test quantum entanglement and Bell nonlocality at an Electron-Ion Collider (EIC). By computing the spin correlations in quark-antiquark pairs produced via photon-gluon fusion, we find that longitudinally polarized photons produce maximal entanglement at leading order, while transversely polarized photons generate significant entanglement near the threshold and in the ultra-relativistic regime. Compared to hadron colliders, the EIC provides a cleaner experimental environment for measuring entanglement through the ${\gamma }^{\ast }g\to q\bar{q}$ channel, offering a strong signal and a promising avenue to verify Bell nonlocality. This study extends entanglement measurements to the EIC, presenting new opportunities to explore the interplay of quantum information phenomena and hadronic physics in the EIC era.

   ↳ hep-phhep-exnucl-exnucl-th+1PRD(2026)·32 citations
2. 02*

   Impact of embedded ${}^{163}$Ho on the performance of the transition-edge sensor microcalorimeters of the HOLMES experiment

   Douglas Bennett🇺🇸 · Matteo Borghesi🇮🇹 · Pietro Campana🇮🇹 · Rodolfo Carobene🇮🇹 · Giancarlo Ceruti🇮🇹 · Matteo De Gerone🇮🇹 · Marco Faverzani🇮🇹 · Lorenzo Ferrari Barusso🇮🇹 · Elena Ferri🇮🇹 · Joseph Fowler🇺🇸 · Sara Gamba🇮🇹 · Flavio Gatti🇮🇹 and 10 other authors

   We present a detailed investigation of the performance of transition-edge sensor (TES) microcalorimeters with ${}^{163}$Ho atoms embedded by ion implantation, as part of the HOLMES experiment aimed at neutrino mass determination. The inclusion of ${}^{163}$Ho atoms introduces an excess heat capacity due to a pronounced Schottky anomaly, which can affect the detector's energy resolution, signal height, and response time. We fabricated TES arrays with varying levels of ${}^{163}$Ho activity and characterized their performance in terms of energy resolution, decay time constants, and heat capacity. The intrinsic energy resolution was found to degrade with increasing ${}^{163}$Ho activity, consistent with the expected scaling of heat capacity. From the analysis, we determined the specific heat capacity of ${}^{163}$Ho to be $(2.9\pm 0.4(\mathrm{stat})\pm 0.7(\mathrm{sys}))$ J/K/mol at $(94\pm 1)$\,mK, close to the literature values for metallic holmium. No additional long decay time constants correlated with ${}^{163}$Ho activity were observed, indicating that the excess heat capacity does not introduce weakly coupled thermodynamic systems. These results suggest that our present TES microcalorimeters can tolerate ${}^{163}$Ho activities up to approximately 5 Bq without significant performance degradation. For higher activities, reducing the TES transition temperature is necessary to maintain energy resolution. These findings provide critical insights for optimizing TES microcalorimeters for future neutrino mass experiments and other applications requiring embedded radioactive sources. The study also highlights the robustness of TES technology in handling implanted radionuclides while maintaining high-resolution performance.

   ↳ physics.ins-detnucl-exEPJC(2025)·3 citations
3. 03*

   Bayesian Quantification of Observability and Equation of State of Twin Stars

   Xavier Grundler🇺🇸 · Bao-An Li🇺🇸

   The possibility of discovering twin stars, two neutron stars (NSs) with the same mass but different radii, is usually studied in forward modelings by using a restricted number of NS matter equation of state (EOS) encapsulating a first-order phase transition from hadronic to quark matter (QM). Informing our likelihood function with the NS radius data from GW170817 and using a meta-model with 9-parameters capable of mimicking most NS EOSs available in the literature, we conduct a Bayesian quantification of the observability and underlying EOSs of twin stars. Of the accepted EOSs, between 12-18\% yield twin stars, depending on the restrictions we place on the second branch. The possibility of twin stars remains robust even under recent observational constraints. We show that many of these twin star scenarios are observable with currently available levels of accuracy in measuring NS radii. We also present the marginalized posterior probability density functions (PDFs) of every EOS parameter for each of four mass-radius correlation topologies. We find that the inferred EOS depends sensitively on not only whether twin stars are present, but also the category of twin stars, indicating that the observation of twin stars would provide a strong constraint on the underlying EOS. In particular, for two coexisting hybrid stars having QM cores at different densities, the PDF for QM speed of sound squared $c_{\mathrm{qm}}^2$ has two peaks, one below and another above the conformal limit $c_{\mathrm{qm}}^2=1/3$ predicted by perturbative QCD.

   ↳ astro-ph.HEastro-ph.GAastro-ph.SRnucl-ex+1PRD(2025)·18 citations
4. 04*

   KHIFC-user friendly program for studying Heavy ion fusion barrier characteristics

   H.C. Manjunatha · P.S. Damodara Gupta · N. Sowmya · K.N. Sridhar

   We have developed an application for studying heavy ion fusion barrier characteristics such as such as fusion barrier heights ($V_B$), positions ($R_B$) and curvature of the inverted parabola ($\hslash \omega$). We call this application as KHIFC (Kolar Heavy Ion fusion barrier Characteristics). This software application hosted in the domain "https://systematics-of-heavy-ion-fusion.vercel.app/". This KHIFC produces fusion cross-sections with the simple input of projectile, target and center of mass energy. The values produced by the KHIFC is validated with experiments. Efficient tools like KHIFC are essential for researchers in nuclear physics, particularly when dealing with complex systems such as actinide and superheavy nuclei. By providing quick calculations and insights, it can significantly aid in experiment planning and theoretical investigations.

   ↳ nucl-thnucl-ex0 citations
5. 05*

   Study of neutron response using time of flight technique in ISMRAN detector

   R. Dey🇮🇳 · P.K. Netrakanti🇮🇳 · D.K. Mishra🇮🇳 · S.P. Behera · R. Sehgal · V. Jha🇮🇳 · L.M. Pant🇮🇳

   We report the measurements of the fast neutron energy response in Indian Scintillator Matrix for Reactor Anti-Neutrinos (ISMRAN) detector consisting of an array of 9$\times$10 Plastic Scintillator Bars (PSBs) at BARC, Mumbai. ISMRAN is an above ground detector setup at $\sim$13 m from the Dhruva reactor core for the detection of reactor anti-neutrinos (${\overline{\text{ensuremath}\nu }}_e$) via the inverse beta decay (IBD) process. The dominant sources of reactor-related background in the vicinity of the detector are high energy $\gamma$-rays and fast neutrons. Therefore, a good understanding of fast neutron response in PSB is an essential pre-requisite for suppression and discrimination of the fast neutron background from IBD events. Kinetic energies of the fast neutron were determined using the Time-of-Flight (TOF) technique, which is used to get the scintillation light yield due to recoiling proton in PSB. We also measured the fast neutron capture time distribution in ISMRAN array using a novel technique involving TOF of the measured fast neutrons. The observed characteristic neutron capture time ( $\tau$ ) of 68.29 $\pm$ 9.48 $\mu$s is in good agreement with GEANT4 based MC simulation. These experimentally measured results will be useful for discriminating correlated and uncorrelated (accidental) background events from the true IBD events in reactor ON and OFF conditions inside the reactor hall.

   ↳ physics.ins-detnucl-exSpringer Proc.Phys.(2023)·0 citations
6. 06*

   Using krypton-83m to determine the neutrino-mass bias caused by a non-constant electric potential of the KATRIN source

   Moritz Machatschek🇩🇪

   Precision spectroscopy of the electron spectrum of the tritium $\beta$ decay near the kinematic endpoint is a direct method to determine the effective electron antineutrino mass. The KArlsruhe TRItium Neutrino (KATRIN) experiment aims to determine this quantity with a sensitivity of better than $0.3\mathrm{eV}$ ($90\%$~C.L.). An inhomogeneous electric potential in the tritium source of KATRIN leads to a distortion of the $\beta$ spectrum, which directly impacts the neutrino-mass observable. This effect can be quantified through precision spectroscopy of the conversion electrons of co-circulated metastable ${}^{83\mathrm{m}}Kr$. This work perturbatively describes the effect of the source potential on the recorded spectra, and thus establishes the leading-order observables of this effect.

   ↳ physics.ins-detnucl-exphysics.data-an1 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.