Electroweak Baryogenesis with Lepton Flavor Violation

TL;DR

This paper explores electroweak baryogenesis within a two-Higgs doublet model incorporating lepton flavor violation, identifying parameter regions that can generate the observed matter-antimatter asymmetry.

Contribution

It demonstrates the potential for lepton flavor violation and extra Yukawa couplings to enhance CP violation and produce baryon asymmetry in a two-Higgs doublet framework.

Findings

Regions with strong first-order phase transition identified

Enhanced CP violation from mu-tau flavor-violating couplings

Marginal baryon asymmetry production with O(1) Yukawa couplings

Abstract

We investigate the feasibility of electroweak baryogenesis in a two-Higgs doublet model with lepton flavor violation. By scrutinizing the heavy Higgs boson mass spectrum, regions satisfying both strong first-order electroweak phase transition and the muon $g-2$ anomaly are identified. We also estimate the baryon number density by exploiting extra Yukawa couplings in the $\mu$-$\tau$ sector. It is found that a CP-violating source term can be enhanced by the $\mu$-$\tau$ flavor-violating coupling together with the extra $\tau$ coupling. With $\mathcal{O}(1)$ Yukawa couplings and CP-violating phases, the observed baryon number density is marginally produced under a generous assumption for the bubble wall profile.