The relic abundance of stable neutralinos is investigated in E8 × E′8 heterotic string theory when supersymnietry is spontaneously broken by hidden-sector gaugino condensates. In the weak coupling regime, very large scalar masses (compared to gaugino masses) are shown to lead to a too large relic abundance of the neutralinos, incompatible with cosmological observations in most of parameter space. The problem does not arise in the strong coupling regime (heterotic M-theory) because there scalar and gaugino masses are generically of the same order of magnitude.
|Journal of High Energy Physics
|Published - 1998
- Dark matter
- Superstrings and heterotic strings