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arXiv · 1904.07795

QED corrections to the big-bang nucleosynthesis reaction rates

Cyril Pitrou·Maxim Pospelov
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Abstract

We compute radiative corrections to nuclear reaction rates that determine the outcome of the Big-Bang Nucleosynthesis (BBN). Any nuclear reaction producing a photon with an energy above $2m_e$ must be supplemented by the corresponding reaction where the final state photon is replaced by an electron-positron pair. We find that pair production brings a typical $0.2 \%$ enhancement to photon emission rates, resulting in a similar size corrections to elemental abundances. The exception is $^4{\rm He}$ abundance, which is insensitive to the small changes in the nuclear reaction rates. We also investigate the effect of vacuum polarisation on the Coulomb barrier, which brings a small extra correction when reaction rates are extrapolated from the measured energies to the BBN Gamow peak energies.

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Cyril Pitrou, Maxim Pospelov. 2020-09-23. QED corrections to the big-bang nucleosynthesis reaction rates. https://doi.org/10.1103/physrevc.102.015803

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