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Nucleon Mass Corrections to the $p \leftrightarrow n$ Rates During Big Bang Nucleosynthesis

David Seckel
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Abstract

The thermal rates for converting neutrons to protons, and vice versa, are calculated, including corrections of order 1 MeV divided by a nucleon mass. The results imply that the primodial helium abundance predicted for big bang nucleosynthesis has been systematically underestimated by about $δY_4 = 0.0012$, i.e., $δY_4 / Y_4 \approx .005$.

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David Seckel. 1993-05-25. Nucleon Mass Corrections to the $p \leftrightarrow n$ Rates During Big Bang Nucleosynthesis. https://arxiv.org/abs/hep-ph/9305311

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