Wed·Dec 31, 2025Wednesday·December 31, 2025

1. 01*

   Big Bang Nucleosynthesis results refined via the Trojan Horse Method

   Roberta Spartà🇮🇹 · Rosario Gianluca Pizzone🇮🇹 · Livio Lamia🇮🇹 · Alessandro Alberto Oliva🇮🇹 · Marco La Cognata🇮🇹 · Alessia Di Pietro🇮🇹 · Pierpaolo Figuera🇮🇹 · Giovanni Luca Guardo🇮🇹 · Marco La Commara🇮🇹 · Dario Lattuada🇮🇹 · Marco Mazzocco🇮🇹 · Sara Palmerini🇮🇹 and 4 other authors

   This work presents the Trojan Horse Method (THM) as a powerful technique for measuring nuclear reaction cross sections at astrophysical energies. We then explore the impact of THM-derived reaction rates on the predictions of Standard Big Bang Nucleosynthesis (SBBN) using the PRIMAT code. Primordial abundances are shown for the single rate impact and, for the first time, also for all the THM rates together. The result shows significant differences with the use of THM rates, which in some cases goes in the direction of improving the agreement with the observations with respect to the use of only reaction rates from direct data, especially for the ${}^7$Li and deuterium abundances, which are still open issues for SBBN.

   nucl-exastro-ph.COnucl-th0 citations
2. 02*

   Nuclear structure properties of ${}^{184-194}$Pb isotopes and isomers

   S. Shukla🇮🇳 · P. C. Srivastava🇮🇳

   In the present work, we study nuclear structure properties of the ${}^{184-194}$Pb isotopes within the framework of the nuclear shell-model. We have performed shell-model calculations using KHH7B and KHHE interactions. We have reported results for energy spectra, electromagnetic properties such as quadrupole moment ($Q$), magnetic moment ($\mu$), $B(E2)$, and $B(M1)$ transition strengths, and compared the shell-model results with the available experimental data. The shell-model results for the half-lives and seniority quantum numbers ($v$) are also reported for the isomeric states.

   ↳ nucl-thnucl-exNPA(2026)·1 citation
3. 03*

   Total Gluon Helicity Contribution to the Proton Spin from Lattice QCD

   Dian-Jun Zhao🇨🇳 · Long Chen🇨🇳 · Hongxin Dong🇨🇳 · Xiangdong Ji🇺🇸 · Liuming Liu🇨🇳 · Zhuoyi Pang🇨🇳 · Andreas Schäfer🇩🇪 · Peng Sun🇨🇳 · Yi-Bo Yang🇨🇳 · Jian-Hui Zhang🇨🇳 · Shiyi Zhong🇨🇳

   We report a state-of-the-art lattice QCD calculation of the total gluon helicity contribution to the proton spin, $\Delta G$. The calculation is done on ensembles with three different lattice spacings $a=\{0.08,0.09,0.11\}$ fm. By employing distillation and momentum smearing for proton external states, we extract the bare matrix elements of the topological current $K^{\mu }$ using 5-HYP smeared Coulomb gauge fixing configurations. Furthermore, we apply a non-perturbative $RI/MOM$ renormalization scheme augmented by the Cluster Decomposition Error Reduction (CDER) technique to determine the renormalization constants of $K^{\mu }$. The results obtained from different components $K^{t,i}$ (with $i$ being the direction of proton momentum or polarization) are consistent with Lorentz covariance within uncertainties. After extrapolating to the continuum limit, $\Delta G$ is found to be $\Delta G=0.231(17{)}^{sta.}(44{)}^{sym.}$ at the $\overline{\mathrm{MS}}$ scale ${\mu }^2=10{\mathrm{GeV}}^2$, which constitutes approximately $46(9)\%$ of the proton spin.

   ↳ hep-lathep-phhep-thnucl-ex+14 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.