Tue·Feb 25, 2025Tuesday·February 25, 2025

1. 01*

   Electromagnetic Form Factors and the Proton Radius Puzzle: A Critical Review of Extraction Methods via Electron-Proton Scattering

   Gerome A. Paterez🇺🇸 · Jade C. Jusoy🇺🇸 · Edmar Pantohan🇺🇸 · Eulogio Auxtero Jr🇺🇸

   The study of protons, fundamental constituents of atomic nuclei, is crucial for understanding nuclear physics and fundamental forces. This review examines advancements in extracting electromagnetic form factors, essential for probing proton structure. Electron-proton scattering experiments, particularly at Jefferson Lab (JLab) and Mainz Microtron (MAMI), have played a key role [arXiv:2009.10510, arXiv:1912.03881]. Various methodologies, such as Rosenbluth separation and polarization transfer, are discussed, highlighting their evolution and challenges, including systematic uncertainties and theoretical ambiguities [arXiv:1706.00696]. Literature indicates the Rosenbluth method yields a proton radius of approximately 0.8 fm, consistent with early measurements but differing from recent polarization transfer results, which suggest a smaller radius [arXiv:1912.03881]. The polarization transfer technique has become a preferred approach, offering precise measurements of the electric-to-magnetic form factor ratio, especially at high momentum transfer [arXiv:1706.00696, arXiv:1912.03881]. Alternative methods, such as cross-section ratios, extend form factor studies but still face residual uncertainties [arXiv:2009.10510]. While significant progress has been made, discrepancies persist, particularly in proton radius extraction. Future research must address systematic uncertainties to refine our understanding of proton electromagnetic properties and advance particle physics [arXiv:1912.03881, arXiv:1706.00696].

   nucl-exnucl-th0 citations
2. 02*

   A systematic study of initial state quark energy loss in fixed target proton nucleus collision

   Sourav Kanti Giri🇮🇳 · Partha Pratim Bhaduri🇮🇳 · Biswarup Paul🇮🇳 · Santosh K. Das🇮🇳

   In this article, we investigate parton energy loss in cold nuclear matter by studying the ratio of Drell-Yan production cross sections in fixed-target proton-nucleus (p + A) collisions. We analyze Drell-Yan production cross-section data from the Fermilab E866 and E906 experiments using two different quark energy loss parametrization models and various parton distribution functions for 800 GeV and 120 GeV proton beams incident on light and heavy nuclear targets. The sensitivity of the energy loss parameter on the employed parton distribution function has been thoroughly investigated. Our results have been used to predict the target mass dependence of Drell-Yan production in upcoming proton-induced collisions at SPS and FAIR.

   ↳ nucl-thnucl-exEPJC(2025)·5 citations
3. 03*

   Calorimetric analysis for long-baseline neutrino experiments

   Kai Gallmeister🇩🇪 · Ulrich Mosel🇩🇪

   In neutrino long-baseline experiments the energy of the incoming neutrino must be reconstructed from observations of the final state. We first discuss the problems that arise for energy conservation during the final-state interactions in a momentum-dependent potential. We then show, for the example of the Deep Underground Neutrino Experiment, that the presence of such a potential is necessarily connected with a large uncertainty in the reconstructed energy. This same uncertainty also affects the determination of energy- and four-momentum-transfers in neutrino-nucleus reactions. We analyze the origins of these uncertainties using transport theory for the description of the evolution of the final state of the reaction. We show that the spectral functions of target nuclei play an essential role not only for the initial neutrino-nucleus interaction but also for the final state evolution.

   ↳ hep-exhep-phnucl-exnucl-thPRD(2025)·4 citations
4. 04*

   Ultra fast, event-by-event heavy-ion simulations for next generation experiments

   Manjunath Omana Kuttan🇩🇪 · Kai Zhou🇨🇳 · Jan Steinheimer🇩🇪 · Horst Stoecker🇩🇪

   We present a novel deep generative framework that uses probabilistic diffusion models for ultra fast, event-by-event simulations of heavy-ion collision output. This new framework is trained on UrQMD cascade data to generate a full collision event output containing 26 distinct hadron species. The output is represented as a point cloud, where each point is defined by a particle's momentum vector and its corresponding species information (ID). Our architecture integrates a normalizing flow-based condition generator that encodes global event features into a latent vector, and a diffusion model that synthesizes a point cloud of particles based on this condition. A detailed description of the model and an in-depth analysis of its performance is provided. The conditional point cloud diffusion model learns to generate realistic output particles of collision events which successfully reproduce the UrQMD distributions for multiplicity, momentum and rapidity of each hadron type. The flexible point cloud representation of the event output preserves full event-level granularity, enabling direct application to inverse problems and parameter estimation tasks while also making it easily adaptable for accelerating any event-by-event model calculation or detector simulation.

   ↳ hep-phhep-exhep-thnucl-ex+1PRC(2025)·6 citations
5. 05*

   Thermoelectric effects of an interacting hadron gas in the presence of an external magnetic field

   Kamaljeet Singh🇮🇳 · Kshitish Kumar Pradhan🇮🇳 · Dushmanta Sahu🇮🇳 · Raghunath Sahoo🇮🇳

   The hot and dense hadronic medium formed during the heavy-ion collisions at the Relativistic Heavy Ion Collider and Large Hadron Collider energies can show thermoelectric effects in the presence of temperature gradients and nonzero baryon chemical potential. In this article, we study the thermoelectric coefficients of an interacting hot and dense hadron gas using the relativistic Boltzmann transport equation under the relaxation time approximation. We discuss the thermoelectric properties within different frameworks of hardon resonance gas models. In the presence of an external magnetic field, the thermoelectric coefficients become anisotropic, which leads to Hall-like thermoelectric coefficients, namely Nernst coefficients, along with the magneto-Seebeck coefficients. For the first time, we also estimate the Thomson coefficient of the medium, which comes into the picture due to the temperature dependence of the Seebeck coefficient of the medium. In the context of studying the thermoelectric generator performance, we calculate the values of the thermoelectric figure of merit of the medium.

   ↳ hep-phhep-exhep-thnucl-ex+1PRD(2025)·9 citations
6. 06*

   Cabibbo-Kobayashi-Maskawa unitarity deficit reduction via finite nuclear size

   M Gorchtein🇩🇪 · V Katyal🇮🇳 · B Ohayon🇮🇱 · B K Sahoo🇮🇳 · CY Seng🇺🇸

   We revisit the extraction of the $|V_{ud}|$ CKM matrix element from the superallowed transition decay rate of ${}^{26m}$Al$\to$${}^{26}$Mg, focusing on finite nuclear size effects. The decay rate dependence on the ${}^{26m}$Al charge radius is found to be four times higher than previously believed, necessitating precise determination. However, for a short-lived isotope of an odd $Z$ element such as ${}^{26m}$Al, radius extraction relies on challenging many-body atomic calculations. We performed the needed calculations, finding an excellent agreement with previous ones, which used a different methodology. This sets a new standard for the reliability of isotope shift factor calculations in many-electron systems. The $\mathcal{F}t$ value obtained from our analysis is lower by $2.2\sigma$ than the corresponding value in the previous critical survey, resulting in an increase in $|V_{ud}{|}^2$ by $0.9\sigma$. Adopting $|V_{ud}|$ from this decay alone reduces the CKM unitarity deficit by one standard deviation, irrespective of the choice of $|V_{us}|$.

   ↳ nucl-thhep-phnucl-exphysics.atom-ph+1PRResearch(2025)·13 citations
7. 07*

   Three-body calculation of deuteron-nucleus scattering using microscopic global optical potential

   A. Deltuva🇱🇹 · D. Jurčiukonis🇱🇹 · D. Likandrovas🇱🇹 · J. Torres Fernandez

   We test microscopic global optical potential in three-body calculations of deuteron-nucleus scattering. We solve Faddeev-type equations for three-body transition operators. We calculate differential cross section and analyzing power for the deuteron elastic scattering and breakup in collisions with ${}^{12}$C, ${}^{16}$O and ${}^{24}$Mg nuclei, and find a reasonable agreement with available experimental data. Comparison with respective predictions using phenomenological optical potentials reveals systematic deviations in particular kinematic regimes.

   ↳ nucl-thnucl-exFew Body Syst.(2024)·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.