Relic neutralino density in scenarios with intermediate unification scale
/ Authors
/ Abstract
We analyse the relic neutralino density in supersymmetric models with an intermediate unification scale. In particular, we present concrete cosmological scenarios where the reheating temperature is as small as 𝒪(1-1000 MeV). When this temperature is associated to the decay of moduli fields producing neutralinos, we show that the relic abundance increases considerably with respect to the standard thermal production. Thus the neutralino becomes a good dark matter candidate with 0.1 ≲ Ωh2 ≲ 0.3, even for regions of the parameter space where large neutralino-nucleon cross sections, compatible with current dark matter experiments, are present. This is obtained for intermediate scales MI ~ 1011-1014 GeV, and moduli masses mϕ ~ 100-1000 GeV. On the other hand, when the above temperature is associated with the decay of an inflaton field, the relic abundance is too small.
Journal: New Journal of Physics