Non-thermal Leptogenesis and a Prediction of Inflaton Mass in a Supersymmetric SO(10) Model

Abstract

The gravitino problem gives a severe constraint on the thermal leptogenesis scenario. This problem leads us to consider some alternatives to it if we try to keep the gravitino mass around the weak scale $m_{3/2}\sim 100$ GeV. We consider, in this paper, the non-thermal leptogenesis scenario in the framework of a minimal supersymmetric SO(10) model. Even if we start with the same minimal SO(10) model, we have different predictions for low-energy phenomenologies dependent on the types of seesaw mechanism. This is the case for leptogenesis: it is shown that the type-I see-saw model gives a consistent scenario for the non-thermal leptogenesis but not for type-II. The predicted inflaton mass needed to produce the observed baryon asymmetry of the universe is found to be $M_I\sim 5\times 10^{11}$ GeV for the reheating temperature $T_R=10^6$ GeV.

Comments: 9 pages, 2 figures; the version to appear in JCAP