Reheating processes after Starobinsky inflation in old-minimal supergravity

TL;DR

This paper investigates the reheating process after Starobinsky inflation within old-minimal supergravity, analyzing decay modes, reheating temperature, and constraints on gravitino and supersymmetry breaking field masses.

Contribution

It provides a detailed analysis of inflaton decay channels, estimates the reheating temperature, and constrains gravitino and supersymmetry breaking field masses in this supergravity framework.

Findings

Reheating temperature estimated at approximately 10^9 GeV.

Allowed gravitino mass range found to be between 10^4 and 10^5 GeV.

Decay into gauge sector dominates the inflaton decay process.

Abstract

We study reheating processes and its cosmological consequences in the Starobinsky model embedded in the old-minimal supergravity. First, we consider minimal coupling between the gravity and matter sectors in the higher curvature theory, and transform it to the equivalent standard supergravity coupled to additional matter superfields. We then discuss characteristic decay modes of the inflaton and the reheating temperature $T_{\rm R}$. Considering a simple model of supersymmetry breaking sector, we estimate gravitino abundance from inflaton decay, and obtain limits on the masses of gravitino and supersymmetry breaking field. We find $T_{\rm R}\simeq 1.0\times10^9$ GeV and the allowed range of gravitino mass as $10^4$ GeV $\lesssim m_{3/2} \lesssim 10^5$ GeV, assuming anomaly-induced decay into the gauge sector as the dominant decay channel.