Hierarchical Neutrinos and Supersymmetric Inflation

TL;DR

This paper presents a model extending the MSSM with a left-right symmetric gauge group that naturally realizes hybrid inflation, solves the mu problem, and explains neutrino masses and baryogenesis within a consistent parameter range.

Contribution

It introduces a novel extension of MSSM incorporating hierarchical neutrino masses, leptogenesis, and inflation, with parameters that are more or less natural.

Findings

Hybrid inflation is naturally realized in the model.

Neutrino masses are explained via the seesaw mechanism.

Parameter ranges satisfy neutrino oscillation and baryogenesis constraints.

Abstract

A moderate extension of MSSM based on a left-right symmetric gauge group, within which hybrid inflation is `naturally' realized, is discussed. The mu problem is solved via a Peccei-Quinn symmetry. Light neutrinos acquire hierarchical masses by the seesaw mechanism. They are taken from the small angle MSW resolution of the solar neutrino puzzle and the SuperKamiokande data. The range of parameters consistent with maximal nu_mu-nu_tau mixing and the gravitino constraint is determined. The baryon asymmetry of the universe is generated through a primordial leptogenesis. The subrange of parameters, where the baryogenesis constraint is also met, is specified. The required values of parameters are more or less `natural'.