Axionic Electroweak Baryogenesis
Abstract
An axion can make the electroweak phase transition strongly first-order as required for electroweak baryogenesis even if it is weakly coupled to the Higgs sector. This is essentially because the axion periodicity naturally allows the structure of phase transition to be insensitive to the axion decay constant that determines the strength of axion interactions. Furthermore, the axion can serve as a CP phase relevant to electroweak baryogenesis if one introduces an effective axion coupling to the top quark Yukawa operator. Then, for between about TeV and order ~TeV, the observed baryon asymmetry can be explained while avoiding current experimental constraints. It will be possible to probe the axion window for baryogenesis in future lepton colliders and beam-dump experiments.
Cite
@article{arxiv.1806.02591,
title = {Axionic Electroweak Baryogenesis},
author = {Kwang Sik Jeong and Tae Hyun Jung and Chang Sub Shin},
journal= {arXiv preprint arXiv:1806.02591},
year = {2019}
}
Comments
5 pages + appendix, 5 figures; PLB published version; a more clear comparison with singlet scalar extension is provided and references are added