Constrains on Kähler moduli inflation from reheating

Abstract

We present predictions of the Kähler moduli inflation model for the spectral tilt by parametrizing the reheating epoch by an effective equation-of-state parameter and the number of e-foldings of reheating; and taking into account the post-inflationary history of the model. This model has an epoch in which the energy density of the universe is dominated by cold moduli particles. We compare our results with data from the Planck mission and find that exotic reheating (with effective equation of state w_re greater than 1 /3 ) or dark radiation is required to match the observations. For canonical reheating case with w_re=0 , we deduce log₁₀(T_re/10³ GeV )≃1190 (n_s-0.956 ). We also analyze our results in the context of observations being planned for the future and their projected sensitivities.