Constraint on the Reheating Temperature from the Decay of the Polonyi Field

Abstract

We study the Polonyi problem in the framework of no-scale type supergravity models. We show that the lightest superparticle (LSP) produced in the decay of the Polonyi field may contribute too much to the present density of the universe. By requiring that LSP should not overclose the universe, we obtain a stringent constraint on the reheating temperature after the decay of the Polonyi field. We calculate the LSP density with physical parameters obtained by solving renormalization group equations in the minimal supersymmetric SU(5) model and find that the reheating temperature should be greater than about 100MeV which corresponds to $O$(100)TeV of the Polonyi mass.