Primordial Nucleosynthesis
arXiv:1208.4748 · doi:10.1088/1742-6596/420/1/012136
Abstract
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 of 4He, D, 3He and 7Li 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 For this purpose, it is now superseded by the analysis of the Cosmic Microwave Background (CMB) radiation anisotropies.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 3-5, between the calculated and observed lithium primordial abundances, that has not been reduced, neither by recent nuclear physics experiments, nor by new observations. We review here the nuclear physics aspects of BBN for the production of 4He, D, 3He and 7Li, but also 6Li, 9Be, 11B and up to CNO isotopes. These are, for instance, important for the initial composition of the matter at the origin of the first stars. 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, like variation of "constants" or alternative theories of gravity.
Invited Plenary Talk given at the 11th International Conference on Nucleus-Nucleus Collisions (NN2012), San Antonio, Texas, USA, May 27-June 1, 2012. To appear in the NN2012 Proceedings in Journal of Physics: Conference Series (JPCS)
References in corpus (18)
- A Bitter Pill: The Primordial Lithium Problem Worsens
- Multiple stellar populations in 47 Tucanae
- Effects of rotation on the evolution of primordial stars
- The primordial abundance of 4He: a self-consistent empirical analysis of systematic effects in a large sample of low-metallicity HII regions
- Coupled Variations of Fundamental Couplings and Primordial Nucleosynthesis
- The Effects of Variations in Nuclear Processes on Type I X-Ray Burst Nucleosynthesis
- Astrophysical S-factor of the 3He(alpha,gamma)7Be reaction measured at low energy via prompt and delayed gamma detection
- Microscopic calculation of the 3He(alpha,gamma)7Be and 3H(alpha,gamma)7Li capture cross sections using realistic interactions
- 3He(alpha,gamma)7Be cross section at low energies
- The 3He + 4He --> 7Be Astrophysical S-factor
- Evaluation of Modern 3He(alpha,gamma)7Be Data
- The 3He(alpha,gamma)7Be S-factor at solar energies: the prompt gamma experiment at LUNA
- Resonant Destruction as a Possible Solution to the Cosmological Lithium Problem
- An MCMC determination of the primordial helium abundance
- High-energy break-up of 6Li as a tool to study the Big-Bang nucleosynthesis reaction 2H(alpha,gamma)6Li
- One fewer solution to the cosmological lithium problem
- Nuclear Reaction Uncertainties, Massive Gravitino Decays and the Cosmological Lithium Problem
- The path to metallicity: synthesis of CNO elements in standard BBN