A Realistic Determination of the Error on the Primordial Helium Abundance: Steps toward Nonparametric Nebular Helium Abundances

  title={A Realistic Determination of the Error on the Primordial Helium Abundance: Steps toward Nonparametric Nebular Helium Abundances},
  author={Keith A. Olive and Evan D. Skillman},
  journal={The Astrophysical Journal},
  pages={29 - 49}
Using the WMAP determination of the baryon density, the standard model of big bang nucleosynthesis yields relatively precise predictions of the primordial light-element abundances. Currently there are two significantly different observational determinations of the primordial helium abundance, and if only statistical errors in 4He abundance determinations are considered, the discrepancies between the observational determinations and the value favored by the WMAP results are significant. Here we… 

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