Galaxy Clusters and Gamma-Ray Lines: Probing Gravitino Dark Matter with the Fermi LAT

TL;DR

This paper investigates the potential of Fermi LAT gamma-ray data to detect signals from decaying gravitino dark matter, focusing on gamma-ray lines and galaxy clusters, and discusses implications for particle physics and future collider experiments.

Contribution

It introduces a novel analysis of Fermi LAT data specifically targeting gravitino decay signatures in gamma-ray lines and galaxy clusters, providing new constraints.

Findings

No gamma-ray line signals detected.

Constraints placed on gravitino decay lifetime.

Implications for next-to-lightest superparticle decay length.

Abstract

If dark matter particles are not perfectly stable, their decay products might be seen in the cosmic-ray fluxes. A natural candidate for decaying dark matter is the gravitino in R-parity violating scenarios. In the relevant GeV-TeV energy range, the Fermi Large Area Telescope (LAT) is now measuring cosmic gamma-ray fluxes with an unprecedented precision. We use the Fermi LAT gamma-ray data to search for signatures from gravitino dark matter particles, concentrating on gamma-ray lines and galaxy cluster observations. Implications of our results for the decay length of the next-to-lightest superparticle, which could be seen at the LHC in the near future, are discussed.