Can thermal inflation be consistent with baryogenesis in gauge-mediated SUSY breaking models?

Abstract

Thermal inflation is an attractive idea to dilute cosmic density of unwanted particles such as moduli fields which cause cosmological difficulties. However, it also dilutes preexisting baryon asymmetry and some viable baryogenesis is necessary for a cosmologically consistent scenario. We investigate whether the Affleck-Dine mechanism can produce baryon asymmetry enough to survive after the dilution in gauge-mediated SUSY breaking models. Flat directions except for $LH_u$ flat direction cannot provide such huge baryon number because of Q-ball formation. We show that although the $LH_u$ flat direction is special in terms of having $\mu$-term which prevents Q-ball formation, it cannot explain the observed baryon asymmetry either.