Primordial Nucleosynthesis

6th Nuclear Physics in Astrophysics

物理学;天文学

Coc, A.^1

Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), CNRS/IN2P3, Université Paris Sud 11, UMR 8609, Bâtiment 104, Orsay Campus

F-91405, France^1

关键词: Big Bang model;    Big bang nucleosynthesis;    Cosmic microwave background radiation;    Cosmic microwave backgrounds;    Expansion of the universe;    Orders of magnitude;    Physics experiments;    Primordial nucleosynthesis;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/665/1/012001/pdf
DOI  :  10.1088/1742-6596/665/1/012001

学科分类：天文学(综合)

来源: IOP

【 摘 要 】

Primordial nucleosynthesis, or Big Bang Nucleosynthesis (BBN), is one of the three evidences for the Big-Bang model, together with the expansion of the Universe and the Cosmic Microwave Background. There is a good global agreement over a range of nine orders of magnitude between abundances of4He, D,3He and7Li deduced from observations, and calculated in primordial nucleosynthesis. This comparison was used to determine the baryonic density of the Universe. For this purpose, it is now superseded by the analysis of the Cosmic Microwave Background (CMB) radiation anisotropies. However, there remain, a yet unexplained, discrepancy of a factor ≈3, between the calculated and observed lithium primordial abundances, that has not been reduced, neither by recent nuclear physics experiments, nor by new observations. Big-Bang nucleosynthesis, that has been used, to first constrain the baryonic density, and the number of neutrino families, remains, a valuable tool to probe the physics of the early Universe.