We address the question of how light the lightest supersymmetric particle neutralino can be to be a reliable cold dark matter (CDM) particle candidate. To this end we perform a combined analysis of the parameter space of the minimal supersymmetric standard model (MSSM) taking into account cosmological and accelerator constraints including those from the radiative b→sγ decay. Appropriate grand unification (GUT) scenarios are considered. We find that the relaxation of gaugino mass unification is sufficient to obtain a phenomenologically and cosmologically viable solution of the MSSM with a neutralino as light as 3 GeV. We find good prospects for the direct detection of these superlight CDM neutralinos via elastic scattering off various nuclei in the forthcoming experiments with low-threshold DM detectors. In a certain sense, these experiments can probe the gaugino mass unification giving constraints on the possible GUT scenarios within the MSSM.
|Number of pages||12|
|Journal||Physical Review D - Particles, Fields, Gravitation and Cosmology|
|Publication status||Published - 1997|
ASJC Scopus subject areas
- Nuclear and High Energy Physics
- Physics and Astronomy (miscellaneous)