Gravitino constraints on supergravity inflation

Abstract

Supergravity embedding of the Standard Model of particle physics provides phenomenologically well-motivated and observationally viable inflationary scenarios. We investigate a class of inflationary models based on the superconformal framework of supergravity and discuss constraints from the reheating temperature, with the particular focus on the gravitino problem inherent in these scenarios. We point out that a large part of the parameter space within the latest BICEP/Keck 95\% confidence contour may have been excluded by the gravitino constraints, depending on the mass scale of the inflaton. Precision measurements of the scalar spectral index by a future mission may rule out some of these scenarios conclusively.