Dynamical Matter-Parity Breaking and Gravitino Dark Matter

Understand

Scenarios where gravitinos with GeV masses make up dark matter are known to be in tension with high reheating temperatures, as required by e.g.

• thermal leptogenesis.
• This tension comes from the longevity of the NLSPs, which can destroy the successful predictions of the standard primordial nucleosynthesis.
• However, a small violation of matter parity can open new decay channels for the NLSP, avoiding the BBN problems, while being compatible with experimental cosmic-ray constraints.