Stellar weak-interaction rates for $rp$-process waiting-point nuclei from projected shell model
Abstract
We propose a projected shell model (PSM) for description of stellar weak-interaction rates between even-even and odd-odd nuclei with extended configuration space where up to six-quasiparticle (qp) configurations are included, and the stellar weak-interaction rates for eight -process waiting-point (WP) nuclei, Ge, Se, Kr, Sr, Zr, Mo, Ru and Pd, are calculated and analyzed for the first time within the model. Higher-order qp configurations are found to affect the underlying Gamow-Teller strength distributions and the corresponding stellar weak-interaction rates. Under -process environments with high temperatures and densities, on one hand, thermal population of excited states of parent nuclei tends to decrease the stellar decay rates. On the other hand, the possibility of electron capture (EC) tends to provide increasing contribution to the rates with temperature and density. The effective half-lives of WP nuclei under the -process peak condition are predicted to be reduced as compared with the terrestrial case, especially for Ge and Se.
Cite
@article{arxiv.2308.11297,
title = {Stellar weak-interaction rates for $rp$-process waiting-point nuclei from projected shell model},
author = {Zi-Rui Chen and Long-Jun Wang},
journal= {arXiv preprint arXiv:2308.11297},
year = {2023}
}