We include corelations between elemental abundances in a Monte Carlo statistical analysis of big bang nucleosynthesis (BBN) predictions, which, along with updated reaction rates and an improved BBN code, lead to tightened constraints on ΩB and Nν. Observational upper limits on the respective primordial He4 and D+3He fractions of 24% (by mass) and 10-4 lead to the limits 0.0097h-2≤ΩB≤0.011h-2 and Nν≤3.04. The former argues against purely baryonic galactic halo dark matter, while the latter could put qualitatively new constraints on neutrinos and new physics. Systematic uncertainties in the inferred primordial abundances of He4 and D+3He are required to relax these constraints.
ASJC Scopus subject areas
- Physics and Astronomy(all)