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GravitinoPack and late decays involving gravitinos

In this talk, we present the package GravitinoPack that calculates decays of unstable supersymmetric particles, involving gravitinos in the final or initial state. If the gravitino is the dark matter particle and therefore stable, the package calculates the decays of the lightest neutralino, and the lighter stau or stop NLSP into the gravitino LSP and one or two Standard Model particles. On the other hand, assuming that the gravitino is unstable, GravitinoPack calculates all its two-body and the three-body decay widths to the neutralino LSP and Standard Model particles. Since all these decays, involving the gravitino, are of gravitational nature, the lifetime of the decaying particle can be of the order of seconds are more, hence called "late decays". The precise knowledge of all these partial decay widths enables the user to apply accurately the relevant cosmological constraints.