There are good reasons to consider models of low-energy supersymmetry with very light photinos and gluinos. In most of these models the lightest R-odd, color-singlet state containing a gluino, the R0, has a mass in the 1-2 GeV range and the slightly lighter photino γ would survive as the relic R-odd species. For the light photino masses considered here, previous calculations resulted in an unacceptable photino relic abundance. But we point out that processes other than photino self-annihilation determine the relic abundance when the photino and R0 are close in mass. Including R0 ↔ γ processes, we find that the photino relic abundance is most sensitive to the R0-to-γ mass ratio, and within model uncertainties, a critical density in photinos may be obtained for an R0-to-γ mass ratio in the range 1.2 to 2.2. We propose photinos in the mass range of 500 MeV to 1.6 GeV as a dark matter candidate, and discuss a strategy to test the hypothesis.
|Original language||English (US)|
|Number of pages||12|
|Journal||Physical Review D - Particles, Fields, Gravitation and Cosmology|
|State||Published - 1996|
ASJC Scopus subject areas
- Nuclear and High Energy Physics
- Physics and Astronomy (miscellaneous)