Supersymmetric cosmology with a gauge singlet

Cosmological constraints on a supersymmetric version of the standard model coupled to N=1 supergravity are derived, in which gauge symmetry breaking is triggered by a Higgs singlet. Possible neutralino dark matter candidates are emphasized. In particular, the fermionic partner of the Higgs singlet is often the lightest supersymmetric particle, with a relic abundance near the critical closure density. (orig.)