Gamma-ray detection from gravitino dark matter decay in the $\mu \nu$SSM

KI-YOUNG CHOI, DANIEL E. LOPEZ -FOGLIANI , CARLOS MUÑOZ AND ROBERTO RUIZ DE AUSTRI

JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS

IOP PUBLISHING LTD

Lugar: Londres; Año: 2012 vol. 1003 p. 1 - 16

1475-7516

The $\mu \nu$SSM provides a solution to the µ-problem of the MSSM and explains the origin of neutrino masses by simply using right-handed neutrino superfields. Given that R-parity is broken in this model, the gravitino is a natural candidate for dark matter since its lifetime becomes much longer than the age of the Universe. We consider the implications of gravitino dark matter in the $mu u$SSM, analyzing in particular the prospects for detecting gamma rays from decaying gravitinos. If the gravitino explains the whole dark matter component, a gravitino mass larger than 20 GeV is disfavored by the isotropic diffuse photon background measurements. On the other hand, a gravitino with a mass range between 0.1 - 20 GeV may give rise to a signal that can be observed by the FERMI satellite. In this way important regions of the parameter space of the $mu u$SSM can be checked.