Revised uncertainties in Big Bang Nucleosynthesis

Big Bang Nucleosynthesis (BBN) explores the first few minutes of nuclei formation during the Big Bang. We present updated 2σ 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 uncertainties as a function of the baryon-to-photon ratio. Reaction rates were updated to those of NACRE, REACLIB, and R-Matrix calculations. The results were then used to derive a new constraint on the effective number of neutrinos.