Leptogenesis from Additional Higgs Doublets

TL;DR

This paper proposes a novel leptogenesis mechanism involving extra Higgs doublets that generate asymmetry at finite temperature through kinematically forbidden cuts, with resonant enhancement not requiring neutrino mass degeneracy.

Contribution

It introduces a new leptogenesis scenario using additional Higgs doublets and finite temperature effects, differing from traditional neutrino degeneracy approaches.

Findings

Resonant enhancement occurs with suppressed Yukawa and self-interactions.

Finite temperature effects enable kinematically forbidden cuts to contribute.

The mechanism does not rely on neutrino mass degeneracy.

Abstract

Leptogenesis may be induced by the mixing of extra Higgs doublets with experimentally accessible masses. This mechanism relies on diagrammatic cuts that are kinematically forbidden in the vacuum but contribute at finite temperature. A resonant enhancement of the asymmetry occurs generically provided the dimensionless Yukawa and self-interactions are suppressed compared to those of the Standard Model Higgs field. This is in contrast to typical scenarios of Resonant Leptogenesis, where the asymmetry is enhanced by imposing a degeneracy of singlet neutrino masses.