Investigation of Neutron Capture Reaction on 93–96Zr Isotopes in the Stellar Environment

Abstract

This study presents a comprehensive theoretical analysis of neutron capture reactions on the zirconium isotopes \(^{93 - 96}\)Zr under stellar conditions relevant to the s-process of nucleosynthesis. Using the Hauser–Feshbach formalism as implemented in the TALYS v2.1 code, Maxwellian-averaged cross sections (MACS) were calculated over a thermal energy range of kT = 5–100 keV, with particular focus on kT = 30 keV. Various combinations of nuclear level density and photon strength function models were tested, including both phenomenological and microscopic approaches. The empirically tuned Brink–Axel model consistently yielded the closest agreement with available experimental data across all isotopes. Among the microscopic models, the Skyrme HFB + QRPA framework emerged as the most robust, reproducing MACS values within 10–30% of experimental measurements. The Kopecky–Uhl model significantly underestimated cross sections for all reactions studied. These findings emphasize the critical importance of accurate nuclear input selection for reliable modeling of neutron capture rates in astrophysical environments.