Gravitino DM and high reheating temperatures after LHC 7/8

TL;DR

This paper examines how high reheating temperatures impact gravitino dark matter models, especially considering LHC constraints on long-lived charged particles, and identifies narrow conditions under which such models remain viable.

Contribution

It provides a detailed analysis of the parameter space for gravitino dark matter with a stau NLSP under high reheating temperatures, incorporating recent experimental constraints.

Findings

High reheating temperatures (>10^9 GeV) are only compatible with gravitino DM in very specific parameter regions.

LHC searches for heavy stable charged particles strongly constrain these scenarios.

Viable models require fine-tuned conditions to satisfy all constraints.

Abstract

The presence of high reheating temperatures in the thermal history of the universe challenges supersymmetric scenarios owing to the gravitino problem. We revise a general R-parity conserving gravitino dark matter scenario with a stau as the next-to-lightest superparticle being particularly constrained by searches for heavy stable charged particles at the LHC. Imposing a variety of experimental and theoretical constraints we show that points with T_R > 10^9 GeV survive only in a very particular corner of parameter space.