We consider the phenomenological implications of gravitino dark matter in the context of the µvSSM. The latter is an R-parity breaking model which provides a solution to the µ- problem of the MSSM and explains the origin of neutrino masses by simply using right-handed neutrino superfields. In particular,we analyze the prospects for detecting gamma rays fromdecaying gravitinos. Gravitino masses larger than 20 GeV are disfavored by the isotropic diffuse photon background measurements, but a gravitino with a mass range between 0.1−20 GeV gives rise to a signal that might easily be observed by the FERMI satellite. Through this kind of analysis important regions of the parameter space of the mnSSM can be checked.

This work was supported in part by the Spanish MICINN under grants FPA2006-01105 and FPA2006-05423, by the Comunidad de Madrid under grant HEPHACOS P-ESP-00346, and by the European Union under the RTN program MRTN-CT-2004-503369. We also thank the ENTApP Network of the ILIAS project RII3-CT-2004-506222 and the UniverseNet Network MRTN-CT-2006-035863.

7 pages, 2 figures.-- PACS: 95.35.+d, 12.60.Jv

Peer reviewed