The Big Bang Nucleosynthesis abundances of the light elements using improved thermonuclear reaction rates

TL;DR

This paper updates Big Bang Nucleosynthesis calculations using improved thermonuclear reaction rates from the NACRE database, resulting in a 7.1% increase in the predicted primordial Lithium abundance.

Contribution

It introduces updated reaction rates into BBN models, refining the predicted light element abundances with a focus on Lithium.

Findings

Primordial Lithium abundance increased by 7.1% with new reaction rates.

Updated reaction rates improve BBN model accuracy.

Results help reconcile theoretical predictions with observations.

Abstract

Big Bang Nucleosynthesis (BBN) is an important stage of a homogeneous and isotropic expanding universe. The results of calculation of the synthesis of light elements during this epoch can then be compared with the abundances of the light elements. The theoretical calculation of the BBN model depends on the initial conditions of the early universe and reaction cross sections measured by the nuclear physics experiment. Recently, an update of the NACRE (Nuclear Astrophysics Compilation of REactions) database is presented. This improved compilation comprises thermonuclear reaction rates for 34 two-body reactions on light nuclides (fifteen are particle transfer reactions and nineteen are radiative capture reactions). In this work, we calculate the BBN abundances by using these updated thermonuclear reaction rates in the framework of the code \texttt{AlterBBN}. Our results suggest that the new numerical result of the primordial Lithium abundance is 7.1 percent larger than the previous calculation.