The Minimal Type-II Seesaw Model and Flavor-dependent Leptogenesis

TL;DR

This paper proposes a minimal Type-II seesaw model with one heavy neutrino to explain neutrino masses and mixing, and demonstrates its ability to generate the observed baryon asymmetry through flavor-dependent leptogenesis.

Contribution

It introduces a minimal Type-II seesaw framework with a specific neutrino mass texture that naturally leads to tri-bimaximal mixing and explains baryon asymmetry via flavored leptogenesis.

Findings

The model accommodates zero neutrino mass scenarios consistent with experimental data.

It successfully accounts for the cosmological baryon asymmetry through electron-flavor leptogenesis.

The neutrino mass matrix can be realized with a minimal particle content.

Abstract

Current experimental data allow the zero value for one neutrino mass, either m_1 =0 or m_3 =0. This observation implies that a realistic neutrino mass texture can be established by starting from the limit (a) m_1 = m_2 =0 and m_3 \neq 0 or (b) m_1 = m_2 \neq 0 and m_3 =0. In both cases, we may introduce a particular perturbation which ensures the resultant neutrino mixing matrix to be the tri-bimaximal mixing pattern or its viable variations. We find that it is natural to incorporate this kind of neutrino mass matrix in the minimal Type-II seesaw model with only one heavy right-handed Majorana neutrino N. We show that it is possible to account for the cosmological baryon number asymmetry in the m_3 =0 case via thermal leptogenesis, in which the CP-violating asymmetry of N decays is attributed to the electron flavor.