The mu problem and sneutrino inflation

TL;DR

This paper explores sneutrino-driven inflation within a supersymmetric model featuring PQ symmetry breaking, addressing the mu problem, neutrino masses, and cosmological issues like gravitino overproduction and baryogenesis.

Contribution

It introduces a model where RH sneutrino inflation and thermal inflation solve multiple cosmological problems simultaneously, linking flaton dynamics to neutrino and mu-term generation.

Findings

Predicts spectral index n_s ≈ 0.96

Achieves correct dark matter abundance from 100 keV gravitino

Provides a viable baryogenesis mechanism via Affleck-Dine leptogenesis

Abstract

We consider sneutrino inflation and post-inflation cosmology in the singlet extension of the MSSM with approximate Peccei-Quinn(PQ) symmetry, assuming that supersymmetry breaking is mediated by gauge interaction. The PQ symmetry is broken by the intermediate-scale VEVs of two flaton fields, which are determined by the interplay between radiative flaton soft masses and higher order terms. Then, from the flaton VEVs, we obtain the correct mu term and the right-handed(RH) neutrino masses for see-saw mechanism. We show that the RH sneutrino with non-minimal gravity coupling drives inflation, thanks to the same flaton coupling giving rise to the RH neutrino mass. After inflation, extra vector-like states, that are responsible for the radiative breaking of the PQ symmetry, results in thermal inflation with the flaton field, solving the gravitino problem caused by high reheating temperature. Our model predicts the spectral index to be n_s\simeq 0.96 due to the additional efoldings from thermal inflation. We show that a right dark matter abundance comes from the gravitino of 100 keV mass and a successful baryogenesis is possible via Affleck-Dine leptogenesis.