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arXiv · 2304.13999

Baryogenesis from sphaleron decoupling

Muzi Hong·Kohei Kamada·Jun'ichi Yokoyama
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Abstract

The electroweak sphaleron process breaks the baryon number conservation within the realms of the Standard Model of particle physics (SM). Recently, it is pointed out that its decoupling may provide the out-of-equilibrium condition required for baryogenesis. In this paper, we study such a scenario taking into account the baryon-number wash-out effect of the sphaleron itself to improve the estimate. We clarify the amount of CP violation required for this scenario to explain the observed asymmetry.

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Muzi Hong, Kohei Kamada, Jun'ichi Yokoyama. 2023-04-27. Baryogenesis from sphaleron decoupling. https://doi.org/10.1103/physrevd.108.063502

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