Fri·Aug 8, 2025Friday·August 8, 2025

1. 01*

   Ab Initio Study of ${}^7$Li with Coupled Mass Partitions

   Jakub Herko (1, 2 and 3)🇺🇸 · Konstantinos Kravvaris (3)🇺🇸 · Petr Navrátil (1 and 4)🇨🇦 · Sofia Quaglioni (3)🇺🇸 · Guillaume Hupin (5)🇫🇷 · Mark A. Caprio (2) ((1) TRIUMF, (2) Department of Physics and Astronomy, University of Notre Dame, (3) Lawrence Livermore National Laboratory, (4) University of Victoria, (5) Université Paris-Saclay, CNRS/IN2P3, IJCLab)🇺🇸

   Background: Lithium is of broad interest in nuclear astrophysics, fusion energy research, and nuclear technology. From a theoretical perspective, the nucleus ${}^7$Li presents a remarkable challenge, as its bound and resonant states can exhibit contributions from both the ${}^4$He + ${}^3$H cluster configuration and configurations involving a neutron or proton coupled to a ${}^6$Li or ${}^6$He core, respectively. Purpose: We aim to achieve a unified ab initio description of bound-state and continuum properties of ${}^7$Li by explicitly including simultaneously the coupled mass/charge partitions ${}^4$He + ${}^3$H, ${}^6$Li + $n$, and ${}^6$He + $p$. Specifically, we investigate the effect of inter-partition coupling on the spectrum of ${}^7$Li and calculate cross sections for the ${}^6$Li($n,p{)}^6$He, ${}^6$He($p,n{)}^6$Li, and ${}^6$He($p,t{)}^4$He reactions. Method: We employ the no-core shell model with continuum for the first time in a calculation that couples three mass/charge partitions of the aggregate nucleus ${}^7$Li, using a chiral nucleon-nucleon interaction as input. Results: The calculated spectrum reproduces all the experimentally observed states of ${}^7$Li in the correct order and predicts additional resonances. The calculation also reproduces the overall energy dependence of the ${}^6$Li$(n,p{)}^6$He cross section. Improved agreement with measured cross sections is obtained after phenomenological adjustment of resonance energies. Conclusions: The present results show that coupling the relevant mass/charge partitions is important for a consistent description of the ${}^7$Li spectrum and reaction cross sections, and offers a useful framework for interpreting existing data and guiding future measurements.

   ↳ nucl-thnucl-exPRC(2026)·1 citation
2. 02*

   Analysis of (p,$\gamma$) capture cross-sections relevant to p-process using TALYS for A=75-110

   Satabdi Mondal🇺🇸 · Enakshi Senapati · Deepak Pandit🇮🇳 · Balaram Dey · Pampa Das🇮🇳 · Alokkumar De🇺🇸 · Srijit Bhattacharya

   The proton capture (p, $\gamma$) cross-sections for eight different atomic nuclei in the mass region A=75-110 were calculated within the nuclear reaction model code TALYS. For all the reactions, we tested different combinations of inputs for level density (l.d) parameter and gamma strength function (${\gamma }_{sf}$). Finally, it was observed that application of hybrid input in TALYS (macroscopic l.d and microscopic or semi-microscopic ${\gamma }_{sf}$ or in abbreviation mac-mic) resulted successful agreement of theoretical prediction with the existing experimental data. Isospin correction was also incorporated in a few cases which improved the matching if the centre of mass energy reaches the threshold energy of the opening of (p,n) channel. The corresponding thermonuclear reaction rates were calculated for all the nuclei and some discrepancies were found with the prediction of the NON-SMOKER code. Using the particular mac-mic input combination, the cross-section and reaction rate for the nuclei ${}^{92}$Nb and ${}^{92}$Mo are calculated within TALYS. These two nuclei lack experimental data but are highly important for understanding early solar system processes. This is a rare attempt to explain the p-capture cross-section of different p-nuclei (A=75-110 range) with similar set of input combinations in TALYS, which may help to remove the uncertainty generated due to the variation of input parameters within nuclear statistical model code

   ↳ nucl-thnucl-exIJMPE(2026)·0 citations
3. 03*

   Probing surface vibration of spherical nuclei in relativistic heavy-ion collisions

   Kouichi Hagino🇯🇵 · Masakiyo Kitazawa🇯🇵

   There has been increasing interest in recent years in using relativistic heavy-ion collisions to probe nuclear structure, such as static nuclear deformation. Here we discuss the role of quantum zero-point fluctuations of the surface vibration of spherical nuclei in relativistic heavy-ion collisions. To this end, we employ an approach to describe the vibration in the space-fixed frame, which has been well established in the field of low-energy heavy-ion fusion reactions. We particularly consider the quadrupole vibration of ${}^{58}$Ni in ${}^{58}$Ni+${}^{58}$Ni reaction and the octupole vibration of ${}^{208}$Pb in ${}^{208}$Pb+${}^{208}$Pb reaction. We show that the surface vibration leads to comparable eccentricity parameters to those for static deformation, while they give significantly different distributions of the initial states, suggesting the importance of the proper treatment of the surface vibration in heavy-ion collisions. We perform similar analysis also for triaxial deformation and gamma-soft vibration.

   ↳ nucl-thhep-phnucl-exPRC(2025)·10 citations
4. 04*

   Weak interaction rates of $sd$-shell Urca pairs in stellar environment using a shell-model approach

   Shweta Sharma🇮🇳 · Praveen C. Srivastava🇮🇳 · Toshio Suzuki🇯🇵

   In this work, the weak interaction rates of $sd$-shell nuclei in the hot and dense stellar environment are calculated using the shell model. The {\it ab initio} effective interactions are employed for the calculation of Gamow-Teller strengths and weak rates in addition to the phenomenological interaction. The weak rates are evaluated in a fine grid of density and temperature. The electron capture and ${\beta }^{-}$-decay rates of Urca pairs of nuclei with $A=23,25,29,31$ and 33 are evaluated as a function of ${\log }_{10}\rho Y_e$ and the corresponding Urca density is obtained. The screening effects are also included for the evaluation of these stellar weak rates. In addition, the intrinsic cooling strength is evaluated for $A=29,31$ and 33 Urca pairs in neutron star crusts. The stellar weak rates, along with the neutrino energy emitted and the gamma heat production, are tabulated for $A=29-39$ nuclei.

   ↳ nucl-thnucl-exPRC(2025)·3 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.