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arXiv · 1902.07220

Equilibration of right-handed electrons

Dietrich Bodeker·Dennis Schroder
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Abstract

We study the equilibration of right-handed electrons in the symmetric phase of the Standard Model. Due to the smallness of the electron Yukawa coupling, it happens relatively late in the history of the Universe. We compute the equilibration rate at leading order in the Standard Model couplings, by including gauge interactions, the top Yukawa- and the Higgs self-interaction. The dominant contribution is due to $ 2 \to 2 $ particle scattering, even though the rate of (inverse) Higgs decays is strongly enhanced by multiple soft scattering which is included by Landau-Pomeranchuk-Migdal (LPM) resummation. Our numerical result is substantially larger than approximations presented in previous literature.

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Dietrich Bodeker, Dennis Schroder. 2019-02-19. Equilibration of right-handed electrons. https://arxiv.org/abs/1902.07220

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