The comparative role of 7Li(n,{\gamma}) reaction in primordial nucleosynthesis

TL;DR

This study models the 7Li(n,γ) reaction using a modified potential cluster approach to accurately describe cross sections relevant for primordial nucleosynthesis, highlighting its dominant role at certain temperatures.

Contribution

The paper introduces a modified potential cluster model with forbidden states to describe neutron capture on 7Li, providing improved cross section calculations for nucleosynthesis.

Findings

The model accurately reproduces experimental cross sections from 5 meV to 1 MeV.

The reaction rate for 7Li(n,γ)8Li was calculated and analytically approximated.

The 7Li(n,γ)8Li reaction dominates over other reactions at T9 < 0.1-0.2.

Abstract

Within the framework of the modified potential cluster model with forbidden states and their classification according to Young diagrams, the possibility of describing experimental data on the total cross sections of the neutron radiative capture on 7Li is considered. It is shown that the model used and the methods for constructing potentials make it possible to correctly describe the behavior of experimental cross sections at energies of 5 meV (5 10-3 eV) to 1 MeV(1 10+6 eV), where experimental data are available. Based on the obtained total cross sections up to 5 MeV, the reaction rate was calculated and its analytical approximation was carried out. It was shown that the 7Li(n,g)8Li reaction dominates at T9 < 0.1-0.2 as against with the burning of 7Li in reactions 7Li(3H,n)9Be and 7Li(4He,g)11B.