TY - JOUR
T1 - Light gravitinos as mixed dark matter
AU - Borgani, Stefano
AU - Masiero, Antonio
AU - Yamaguchi, Masahiro
N1 - Funding Information:
One of the authors (M.Y.) is grateful to S. David-son and G. Raffelt for helpful discussions, especially on constraintso n the R-parity violation. A.M. thanks G. Giudice for useful commentso n models with low-energy SUSY breaking. The work of M.Y. was sup-portedi n part by the Sonderforschungsbereich3 75-95: “Research in Particle-Astrophysics” of the Deutsche Forschungsgemeinschafat nd the ECC under contracts No. SCl-CT9 l-0729 and No. SC 1-(X92-0789.
PY - 1996/10/3
Y1 - 1996/10/3
N2 - 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.
AB - 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.
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U2 - 10.1016/0370-2693(96)00956-2
DO - 10.1016/0370-2693(96)00956-2
M3 - Article
AN - SCOPUS:0041624120
SN - 0370-2693
VL - 386
SP - 189
EP - 197
JO - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
JF - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
IS - 1-4
ER -