English

Big Bang Nucleosynthesis updated with the NACRE Compilation

Astrophysics 2016-08-30 v2

Abstract

We update the Big Bang Nucleosynthesis calculations on the basis of the recent NACRE compilation. The average values of the calculated abundances of light nuclei do not differ significantly from that obtained using the previous Fowler's compilation. 7Li{^7}Li is slightly depressed at high baryon to photon ratio η\eta. The main uncertainty concerns the D(p,γ)3HeD(p,\gamma){^3}He reaction rate affecting the synthesis of 7Li{^7}Li (via the 3He(α,γ)7Be(eν)7Li{^3}He(\alpha,\gamma){^7}Be(e\nu){^7}Li) at rather high baryonic density. On the left part of the lithium valley the uncertainty is strongly reduced due to the improvement of the measurement of the T(α,γ)7LiT(\alpha,\gamma)^{7}Li reaction rate. We use lithium-7 as the main baryometer, since, though much efforts have been devoted to the determination of Deuterium in absorbing clouds in the line of sight of remote quasars, the statistics is very poor compared to the long series of lithium measurements. Taking into account the lithium constraints, two possible baryonic density ranges emerge, η10=1.41.9\eta_{10}= 1.4 - 1.9 and η10=3.35.1\eta_{10} = 3.3 - 5.1. The Be and B abundances produced in the big bang are orders of magnitudes lower, and spallation of fast carbon and oxygen is probably their unique source, in the early Galaxy.

Keywords

Cite

@article{arxiv.astro-ph/0002248,
  title  = {Big Bang Nucleosynthesis updated with the NACRE Compilation},
  author = {Elisabeth Vangioni-Flam and Alain Coc and Michel Casse},
  journal= {arXiv preprint arXiv:astro-ph/0002248},
  year   = {2016}
}

Comments

8 pages, 5 figures, accepted in Astronomy and Astrophysics

R2 v1 2026-07-22T07:44:23.859Z