Transitional CP Violation in the MSSM and Electroweak Baryogenesis

TL;DR

This paper investigates how CP violation in the MSSM's Higgs sector during a first-order electroweak phase transition could generate the universe's baryon asymmetry, demonstrating the feasibility of this mechanism through solving equations of motion.

Contribution

It provides a concrete example of transitional CP violation in the MSSM and explores its potential to produce baryon asymmetry via tau lepton interactions.

Findings

Transitional CP violation can be realized in the MSSM during the phase transition.

Explicit CP breaking in the Higgs sector can be consistent with experimental bounds.

Baryon asymmetry may be generated through tau lepton interactions at the bubble wall.

Abstract

Electroweak baryogenesis depends on the profile of the bubble wall created in the first-order phase transition. It is pointed out that CP violation in the Higgs sector of the MSSM could become large enough to explain the baryon asymmetry. We confirm this by solving the equations of motion for the Higgs fields with the effective potential at the transition temperature. That is, we present an example such that the transitional CP violation is realized and show the possibility that the baryon asymmetry of the universe may be produced, if marginally, by the $\tau$ lepton interacting with the wall, when an explicit CP breaking in the Higgs sector, which is consistent with experimental bounds, is induced at the phase transition.