T-Model Higgs Inflation in Supergravity

TL;DR

This paper presents a simple, natural supergravity inflation model using the Higgs field for spontaneous U(1)_(B-L) breaking, compatible with observations and connecting to MSSM phenomenology.

Contribution

It introduces a new T-model of Higgs inflation in supergravity with a specific Kahler potential and superpotential, linking inflation to particle physics and baryogenesis.

Findings

Spectral index ns close to current observational value

Tensor-to-scalar ratio r increases with N<36

Model explains mu parameter and supports non-thermal leptogenesis

Abstract

We focus on a simple, natural and predictive T model of inflation in Supergravity employing as inflaton the Higgs field which leads to the spontaneous breaking of a U(1)_(B-L) symmetry at the SUSY GUT scale. We use a renormalizable superpotential, fixed by a U(1) R symmetry, and a Kahler potential which parameterizes the Kahler manifold SU(2,1)/(SU(2)xU(1))x(SU(2)/U(1)) with scalar curvature R_K=-6/N+2/N_0 where 0<N_0<6. The spectral index ns turns out to be close to its present central observational value and the tensor-to-scalar ratio r increases with N<36. The model can be nicely linked to MSSM offering an explanation of the magnitude of the mu parameter consistently with phenomenological data. It also allows for baryogenesis via non-thermal leptogenesis with gravitino as light as 1 TeV.