Mon·Oct 28, 2024Monday·October 28, 2024

1. 01*

   Direct determination of the ${}^{235}$U to ${}^{239}$Pu inverse beta decay yield ratio in the power reactor neutrino experiments

   I. Alekseev🇷🇺 · V. Belov🇷🇺 · A. Bystryakov🇷🇺 · M. Danilov🇷🇺 · D. Filosofov🇷🇺 · M. Fomina🇷🇺 · P. Gorovtsov🇷🇺 · Ye. Iusko🇷🇺 · S. Kazartsev🇷🇺 · V. Khvatov🇷🇺 · S. Kiselev🇷🇺 · A. Kobyakin🇷🇺 and 21 other authors

   The yields of the inverse beta decay events produced by antineutrinos from a certain nuclear reactor fuel component are used by many experiments to check various model predictions. Yet measurements of the absolute yields feature significant uncertainties coming, mainly, from the understanding of the antineutrino detection efficiency. This work presents a simple novel approach to directly determine the ${}^{235}$U to ${}^{239}$Pu inverse beta decay yield ratio using the fuel evolution analysis. This ratio can be used for a sensitive test of reactor models, while the proposed method, results in smaller systematic uncertainties. The DANSS result on this ratio is one of the most precise among reactor neutrino experiments, yet does not significantly contradict to any previous measurement.

   nucl-exhep-exPRD(2025)·3 citations
2. 02*

   Comparing effective temperatures in standard, Tsallis, and q-dual statistics from transverse momentum spectra of identified light charged hadrons produced in gold--gold collisions at RHIC energies

   Ting-Ting Duan🇨🇳 · Pei-Pin Yang🇨🇳 · Peng-Cheng Zhang🇨🇳 · Hai-Ling Lao🇨🇳 · Fu-Hu Liu🇨🇳 · Khusniddin K. Olimov🇺🇿

   This study investigates the transverse momentum ($p_T$) spectra of identified light charged hadrons produced in gold--gold (Au+Au) collisions across various centrality classes at center-of-mass energies per nucleon pair, $\sqrt{s_{NN}}$, ranging from 7.7 to 200 GeV, as measured by the STAR Collaboration at the Relativistic Heavy Ion Collider (RHIC). The analysis employs standard (Bose-Einstein/Fermi-Dirac), Tsallis, and q-dual statistics to fit the same $p_T$ spectra and derive distinct effective temperatures: $T_{\text{Standard}}$, $T_{\text{Tsallis}}$, and $T_{\text{q-dual}}$. In most instances, there exists an approximately linear relationship or positive correlation between $T_{\text{Tsallis}}$ and $T_{\text{Standard}}$, as well as between $T_{\text{q-dual}}$ and $T_{\text{Standard}}$, when considering $T_{\text{Standard}}$ as a baseline. However, while both $T_{\text{Tsallis}}$ and $T_{\text{q-dual}}$ increase from semi-central to central Au+Au collisions at 62.4 GeV and 200 GeV, where QGP is expected, changes in $T_{\text{Standard}}$ occur more gradually. This work suggests that $T_{\text{Standard}}$ is better suited for characterizing phase transitions between hadronic matter and QGP compared to $T_{\text{Tsallis}}$ or $T_{\text{q-dual}}$, primarily due to the considerations related to entropy index in the Tsallis and q-dual statistics.

   nucl-exhep-exhep-phnucl-thEur.Phys.J.Plus(2024)·5 citations
3. 03*

   First Experimental Test of the Ratio Method

   S. Ota🇯🇵 · P. Capel🇩🇪 · G. Christian · V. Durant🇩🇪 · K. Hagel🇺🇸 · E. Harris🇺🇸 · R.C. Johnson · Z. Luo · F.M. Nunes🇺🇸 · M. Roosa🇺🇸 · A. Saastamoinen🇺🇸 · D.P. Scriven🇺🇸

   The ratio is a new reaction observable suggested to extract accurately structure information on halo nuclei. It corresponds to the ratio of differential cross sections for scattering and breakup, which is predicted to remove the uncertainty related to the reaction dynamics. We present here the first experimental test of the method for the 11Be + 12C collision at ELab = 20A MeV performed at Texas A&M University. Differential cross sections for scattering and inclusive one-neutron breakup have been measured with the new detector array BlueSTEAl. The ratio of cross sections is very smooth and independent of the projectile-target interaction, which demonstrates the validity of the ratio method. We extend our analysis to existing 11Be + 208Pb data, confirming that the method works well on any target.

   nucl-exnucl-thNPA(2025)·0 citations
4. 04*

   Deciphering the mechanism of $J/\psi$-nucleon scattering

   Bing Wu🇨🇳 · Xiang-Kun Dong🇩🇪 · Meng-Lin Du🇨🇳 · Feng-Kun Guo🇨🇳 · Bing-Song Zou🇨🇳

   The low-energy $J/\psi N$ scattering is important for various reasons: it is related to the hidden-charm $P_c$ pentaquark states, provides insights into the role of gluons in nucleon structures, and is relevant to the $J/\psi$ properties in nuclear medium. The scattering can happen through two distinct mechanisms: the coupled-channel mechanism via open-charm meson-baryon intermediate states, and the soft-gluon exchange mechanism. We investigate the $J/\psi N$ $S$-wave scattering length through both mechanisms, and find that the soft-gluon exchange mechanism leads to a scattering length at least one order of magnitude larger than that from the coupled-channel mechanism and thus is the predominant one. The findings can be verified by lattice calculations and will enhance our understanding of the scattering processes breaking the Okubo-Zweig-Iizuka rule.

   ↳ hep-phhep-latnucl-exnucl-thFund.Res.(2025)·20 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.