Tue·Jun 10, 2025Tuesday·June 10, 2025

1. 01*

   Model Comparisons of Transverse Energy and Charged-Particle Multiplicity in A+A Collisions at Midrapidity from $\sqrt{s_{NN}}$ $=$ 7.7 to 200~GeV

   Niseem Magdy🇺🇸 · Antonio Silva🇺🇸 · Christal Martin🇺🇸 · Josie Hakanson🇺🇸 · Olivia Bartoshesky🇺🇸 · Aidan Hill🇺🇸 · Christine Nattrass🇺🇸

   We present a comprehensive comparison of PHENIX measurements of transverse energy production ($d{E}_T/d\eta$) and charged-particle multiplicity ($dN/d\eta$) at midrapidity to simulations from PYTHIA-8, AMPT, HIJING, and SMASH. These comparisons span both small systems (d+Au, ${}^3$He+Au) and large systems (Cu+Cu, Cu+Au, Au+Au, and U+U) at $\sqrt{s_{NN}}$ $\sim$ 200~GeV and Au+Au over a range of beam energies $\sqrt{s_{NN}}=7.7$--200~GeV. Using the Rivet framework, we assess the performance of these models. While general trends are captured, significant deviations persist, particularly in low-energy and peripheral collisions, underscoring the need for improved modeling of baryon stopping and energy deposition mechanisms.

   nucl-exhep-phnucl-thJ.Phys.G(2025)·0 citations
2. 02*

   Universal Mass Equation for Equal-Quantum Excited-States Sets II

   L. David Roper (VTech)🇺🇸 · Igor Strakovsky (GWU)🇺🇸

   We extend our recent study of the universal mass equation for equal-quantum excited-states sets reported by Roper and Strakovsky~\cite{Roper:2024ovj}. The masses of twelve baryon sets and sixteen meson sets, with only two equal-quantum excited states in each set, using Breit-Wigner PDG2024 masses and their uncertainties at fixed $J^P$ for baryons and $J^{PC}$ for mesons, are fitted by a simple one-parameter logarithmic function, $M_n=\alpha Ln(n)+M_1$, where $n$ is the level of radial excitation. Two accurate masses that start a set are used to calculate four higher masses in the set accurately. It is noted that $\alpha$ values for $b\bar{b}$ equal-quantum excited-states sets accurately lie on a straight line, whose line parameters can be used to calculate $\alpha$ and predict higher mass states for $b\bar{b}$ sets that have only one known member.

   ↳ hep-phhep-exnucl-exnucl-thEPJA(2025)·0 citations
3. 03*

   Removal of spallation-induced tritium from silicon through diffusion

   R. Saldanha🇺🇸 · D. Reading🇬🇧 · P.E. Warwick🇬🇧 · A.E. Chavarria🇺🇸 · B. Loer🇺🇸 · P. Mitra🇺🇸 · L. Pagani🇺🇸 · P. Privitera🇺🇸

   Tritium, predominantly produced through spallation reactions caused by cosmic ray interactions, is a significant radioactive background for silicon-based rare event detection experiments, such as dark matter searches. We have investigated the feasibility of removing cosmogenic tritium from high-purity silicon intended for use in low-background experiments. We demonstrate that significant tritium removal is possible through diffusion by subjecting silicon to high-temperature (> 400C) baking. Using an analytical model for the de-trapping and diffusion of tritium in silicon, our measurements indicate that cosmogenic tritium diffusion constants are comparable to previous measurements of thermally-introduced tritium, with complete de-trapping and removal achievable above 750C. This approach has the potential to alleviate the stringent constraints of cosmic ray exposure prior to device fabrication and significantly reduce the cosmogenic tritium backgrounds of silicon-based detectors for next-generation rare event searches.

   ↳ physics.ins-dethep-exnucl-exPRD(2025)·1 citation
4. 04*

   New Types of Hydrogenlike matter Composed of Electron(s) and Meson(s)

   Jun-Feng Wang🇨🇳 · Zi-Yue Cui🇨🇳 · Cheng-Qun Pang🇨🇳 · Zhi-Feng Sun🇨🇳

   In the present work, we predict the existence of new types of hydrogenlike matter, including hydrogenlike atoms (${\pi }^{+}{e}^{-}$, $K^{+}{e}^{-}$, $D^{+}{e}^{-}$), hydrogenlike molecular ions (${\pi }^{+}{\pi }^{+}{e}^{-}$, $K^{+}{K}^{+}{e}^{-}$, $D^{+}{D}^{+}{e}^{-}$) and hydrogenlike molecules (${\pi }^{+}{\pi }^{+}{e}^{-}{e}^{-}$, $K^{+}{K}^{+}{e}^{-}{e}^{-}$, $D^{+}{D}^{+}{e}^{-}{e}^{-}$). By solving the Schrödinger equation, the binding energy of hydrogenlike atoms is obtained as $E_n=-\frac{1}{2n^2}$. For hydrogenlike molecular ions and molecules, the variational method is employed to calculate the binding energies, i.e., $E_{+}=-0.587$ and $E_0=-1.139$ for hydrogenlike molecular ions and molecules, respectively. And the bond lengths for hydrogenlike molecular ions and molecules are also calculated, whose values are $2.003$ and $1.414$, respectively. Here all the quantities are in atomic units for convenience. In addition, the strong interaction between the two constituent mesons is considered in our calculations, where we find that its influence on the hydrogenlike molecular ions and molecules can be neglected. Comparisons of hydrogenlike molecular ion and molecule with the systems governed by the strong interaction are made, which suggests the possible existence of doubly heavy triquark, hidden heavy-flavor tetraquarks and doubly heavy tetraquarks. Hopefully, these types of matter would be observed in the future with the improvement of accuracy in the high energy physical experiments.

   ↳ hep-phhep-exnucl-exnucl-thFew Body Syst.(2026)·0 citations
5. 05*

   Towards a Global Search for New Physics with Isotope Shifts

   Elina Fuchs🇩🇪 · Fiona Kirk🇩🇪 · Agnese Mariotti🇩🇪 · Jan Richter🇩🇪 · Matteo Robbiati🇮🇹

   Isotope shifts have emerged as a sensitive probe of new bosons that couple to electrons and neutrons, and of nuclear structure. The recent Hz- or even sub-Hz-level isotope shift measurements across different elements call for a global assessment of all available data. In this work, we present the fit framework kifit that for the first time enables a combined analysis of isotope shift data from several elements, taking into account correlations. We provide a thorough comparison of analytical methods and the fit to analyse linear and nonlinear King plots and quantify their uncertainties. Finally, we provide recommendations for future measurements that could enhance the sensitivity to new physics and offer new insights into nuclear structure.

   ↳ physics.atom-phhep-phnucl-exnucl-thPRA(2025)·2 citations
6. 06*

   Tracing the Evolution of Nuclear Excitation at the Electron-Ion Collider

   Niseem Magdy🇺🇸

   We investigate the evolution of nuclear excitation in electron-nucleus (e+A) collisions at the upcoming Electron-Ion Collider (EIC) using the BeAGLE event generator. Leveraging the EIC's unique collider kinematics, we demonstrate the remarkable capability to separate distinct nuclear reaction stages, hard scattering, intranuclear cascade, and nuclear de-excitation, in the laboratory frame. Our systematic analysis reveals that event-by-event fluctuations in the mean transverse momentum (k) are highly sensitive to the intranuclear cascade formation time and nuclear geometry, while minimally affected by variations in electron beam energy. These findings establish k as a robust observable for constraining nuclear excitation mechanisms, providing critical benchmarks for future EIC experiments and guiding theoretical advancements in nuclear transport modeling.

   ↳ hep-phnucl-exnucl-thPRC(2026)·1 citation
7. 07*

   Cryogenic systems for the TUCAN EDM experiment

   Jeffery W. Martin🇨🇦 · B. Algohi🇨🇦 · D. Anthony🇨🇦 · L. Barrón-Palos🇲🇽 · M. Bradley🇨🇦 · A. Brossard🇨🇦 · T. Bui🇨🇦 · J. Chak🇨🇦 · C. Davis🇨🇦 · R. de Vries🇨🇦 · K. Drury🇨🇦 · D. Fujimoto🇨🇦 and 51 other authors

   The TUCAN (TRIUMF UltraCold Advanced Neutron) Collaboration is completing a new ultracold neutron (UCN) source. The UCN source will deliver UCNs to a neutron electric dipole moment (EDM) experiment. The EDM experiment is projected to be capable of an uncertainty of $1\times 10^{-27}e$cm, competitive with other planned projects, and a factor of ten more precise than the present world's best. The TUCAN source is based on a UCN production volume of superfluid helium (He-II), held at 1~K, and coupled to a proton-driven spallation target. The production rate in the source is expected to be in excess of $10^7$~UCN/s; since UCN losses can be small in superfluid helium, this should allow us to build up a large number of UCNs. The spallation-driven superfluid helium technology is the principal aspect making the TUCAN project unique. The superfluid production volume was recently cooled, for the first time, and successfully filled with superfluid helium. The design principles of the UCN source are described, along with some of the challenging cryogenic milestones that were recently passed.

   ↳ physics.ins-detnucl-exEPJ Web Conf.(2025)·4 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.