Leptogenesis is at the heart of particle cosmology which requires physics beyond the Standard Model. There are two possibilities of realizing leptogenesis; thermal and non-thermal. Both are viable given the scale of inflation and the constraint on the reheat temperature. However non-thermal leptogenesis can leave its imprint upon cosmic micro wave background radiation. In this paper we will discuss cosmological constraints on non-thermal leptogenesis scenarios within supersymmetry.
8 pages, shortened version, to appear in PLB. Just one ref. added