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arXiv · 1706.02834

Revised Uncertainties in Big Bang Nucleosynthesis

Michael Foley·Nishanth Sasankan·Motohiko Kusakabe·Grant. J. Mathews
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Abstract

Big Bang Nucleosynthesis (BBN) explores the first few minutes of nuclei formation after the Big Bang. We present updates that result in new constraints at the 2{\sigma} level for the abundances of the four primary light nuclides - D,3He,4He, and 7Li - in BBN. A modified standard BBN code was used in a Monte Carlo analysis of the nucleosynthesis uncertainty as a function of baryon-to-photon ratio. Reaction rates were updated to those of NACRE and REACLIB, and R-Matrix calculations. The results are then used to derive a new constraint on the effective number of neutrinos.

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Michael Foley, Nishanth Sasankan, Motohiko Kusakabe, Grant. J. Mathews. 2017-06-09. Revised Uncertainties in Big Bang Nucleosynthesis. https://doi.org/10.1142/s0218301317410087

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