| Abstract: |
Some variants of the minimal supersymmetric extension of the Standard Model (MSSM) feature a strip in parameter space where the lightest neutralino is identified as the lightest supersymmetric particle (LSP), the gluino is the next-to-lightest supersymmetric particle (NLSP) and is nearly degenerate with the LSP, and the relic cold dark matter density is brought into the range allowed by astrophysics and cosmology by coannihilation with the gluino NLSP. We calculate the relic density along this gluino coannihilation strip in the MSSM, including the effects of gluino-gluino bound states, and taking into account the decoupling of the gluino and LSP densities that occurs for a squark to gluino mass ratio larger than order of 100. We find that the LSP may weigh up to ~ 8 TeV with the correct dark matter density. |
