In theories with a gauge-mediated mechanism of supersymmetry breaking the gravitino is likely to be the lightest superparticle and, hence, a candidate for dark matter. We show that the decay of the next-to-lightest superparticle into a gravitino can yield a non-thermal population of gravitinos which behave as a hot dark matter component. Together with the warm component, which is provided by the population of gravitinos of thermal origin, they can give rise to viable schemes of mixed dark matter. This realization has some specific and testable features both in particle physics and astrophysics. We outline under which conditions the mechanism remains viable even when R-parity is broken.
|Number of pages||9|
|Journal||Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics|
|Publication status||Published - 1996 Oct 3|
ASJC Scopus subject areas
- Nuclear and High Energy Physics