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Effect of Finite Mass on Primordial Nucleosynthesis

Robert E. Lopez·Michael S. Turner·Geza Gyuk
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Abstract

We have calculated the small effect of finite nucleon mass on the weak-interaction rates that interconvert protons and neutrons in the early Universe. We have modified the standard code for primordial nucleosynthesis to include these corrections and find a small, systematic increase in the 4He yield, $δY / Y \simeq (0.47 - 0.50)% $, depending slightly on the baryon-to-photon ratio. The fractional changes in the abundances of the other light elements are a few percent or less for interesting values of the baryon-to-photon ratio.

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Robert E. Lopez, Michael S. Turner, Geza Gyuk. 1997-03-11. Effect of Finite Mass on Primordial Nucleosynthesis. https://doi.org/10.1103/physrevd.56.3191

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