Revised Uncertainties in Big Bang Nucleosynthesis
  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.
