Visible sector inflation and the right thermal history in light of Planck data

TL;DR

This paper explores visible sector inflation models within the MSSM framework, demonstrating their compatibility with Planck data, and discusses how they naturally produce the observed matter content without dark radiation or isocurvature fluctuations.

Contribution

It analyzes MSSM-based inflation models, including flat direction and curvaton scenarios, showing their consistency with current cosmological and collider constraints.

Findings

Visible sector inflaton models match Planck data.

Decay of inflaton produces all relevant degrees of freedom.

Late-decaying curvaton can generate observable non-Gaussianity.

Abstract

Inflation creates perturbations for the large scale structures in the universe, but it also dilutes everything. Therefore it is pertinent that the end of inflation must explain how to excite the Standard Model {\it dof} along with the dark matter. In this paper we will briefly discuss the role of visible sector inflaton candidates which are embedded within the Minimal Supersymmetric Standard Model (MSSM) and discuss their merit on how well they match the current data from the Planck. Since the inflaton carries the Standard Model charges their decay naturally produces all the relevant {\it dof} with no {\it dark/hidden sector radiation} and no isocurvature fluctuations. We will first discuss a single supersymmetric flat direction model of inflation and demonstrate what parameter space is allowed by the Planck and the LHC. We will also consider where the perturbations are created by another light field which decays after inflation, known as a {\it curvaton}. The late decay of the curvaton can create observable non-Gaussianity. In the end we will discuss the role of a {\it spectator} field whose origin may not lie within the visible sector physics, but its sheer presence during inflation can still create all the perturbations responsible for the large scale structures including possible non-Gaussianity, while the inflaton is embedded within the visible sector which creates all the relevant matter including dark matter, but no dark radiation.