Evidence for the reduction of nuclear level density away from the $\beta $-stability line
Abstract
The isospin dependence of nuclear level density has been investigated by analyzing the spectra of evaporated neutrons from excited Sn and Te nuclei. These nuclei are populated via + In and He + Sn reactions in the excitation energy range of 18 - 26 MeV. Because of low excitation energy, the neutron spectra are predominantly contributed by the first-chance decay leading to the -stable Sn and neutron-deficient Te as residues for the two cases. Theoretical analysis of the experimental spectra have been performed within the Hauser-Feshbach formalism by employing different models of the level density parameter. It is observed that the data could only be explained by the level density parameter that decreases monotonically when the proton number deviates from the -stable value. This is also confirmed by performing a microscopic shell-model calculation with the Wood-Saxon mean field. The results have strong implication on the estimation of the level density of unstable nuclei, and calculation of astrophysical reaction rates relevant to - and -processes.
Keywords
Cite
@article{arxiv.2012.04869,
title = {Evidence for the reduction of nuclear level density away from the $\beta $-stability line},
author = {Pratap Roy and K. Banerjee and T. K. Rana and S. Kundu and S. Manna and A. Sen and D. Mondal and J. Sadhukhan and M. T. Senthil Kannan and T. K. Ghosh and S. Mukhopadhyay and Deepak Pandit and G. Mukherjee and S. Pal and D. Paul and K. Atreya and C. Bhattacharya},
journal= {arXiv preprint arXiv:2012.04869},
year = {2020}
}