Decay Characteristics of Neutron Excess Sodium Nuclei

Joseph Bevelacqua

doi:10.32388/1y819a

Abstract

In neutron star mergers, neutron excess nuclei and the r-process are important factors governing the production of heavier nuclear systems. An evaluation of sodium nuclei suggests that the heaviest Z = 11 nucleus will have mass 45 with filling of the 2p1/2 neutron shell. A = 36 – 45 sodium isotopes have limited experimental half-life data, but the model predicts beta decay half-lives in the range of 0.551 – 1.31 ms. Based on previous calculations for Z = 9, 10, 20, 26, and 30 systems, these results likely overestimate the half-lives of A = 36 – 45 neutron excess sodium nuclei.

Highlights

The nucleosynthesis of heavy elements occurs by three basic processes that add protons or neutrons to a nuclear system[1,2]
Neutron capture creates neutron-rich nuclei, and the resulting nuclear systems depend upon the rate of neutron addition and the beta decay rates of the residual nuclei
Neutron excess nuclei occur throughout the Periodic Table, this paper focuses on sodium systems as part of a continuing investigation of neutron excess nuclei that are of potential astrophysical significance[8,9,10,11,12]

Summary

Introduction

The nucleosynthesis of heavy elements occurs by three basic processes that add protons or neutrons to a nuclear system[1,2]. The study of neutron excess systems and their decay properties are significant considerations in understanding the r-process, and its importance in producing the observed elements in the universe. This paper attempts to partially fill the void by calculating the decay properties of neutron excess systems that are important in nucleosynthesis These theoretical studies should assist in planning future experiments associated with neutron excess systems that are far removed from the line of stability. A recent study of fluorine isotopes in intermediate-mass stellar systems16.17 concluded that oxygen fusion could occur at lower densities than initially assumed. This result suggests that intermediate-mass stars are more likely to encounter thermonuclear excursion rather than undergoing gravitational collapse.

Calculational Methodology

Results and Discussion

Conclusions