On the Realization of WIMPflation

Abstract

We consider models for inflation with a stable inflaton. Reheating is achieved through scattering processes such as φφ → hh, where h is the Standard Model Higgs boson. We consider the reheating process in detail and show that for a relatively large coupling (needed for the late annihilations of the inflaton during freeze-out), reheating is almost instantaneous leading to a relatively high reheating temperature. The process φφ ↔ hh brings the inflaton back into equilibrium, leading to a well studied scalar singlet dark matter candidate and Higgs portal model. We argue that such models can be derived from no-scale supergravity.

Freeze-in from Preheating

“…In the case of the weak scale gravitino, the thermal production cross section is independent of the temperature and therefore constant in time, implying a gravitino abundance proportional to T RH . However, when the particle production cross section depends strongly on temperature, σ ∼ T n with n ≥ 6, the abundance depends on the maximum temperature attained during the reheating process [17][18][19][21][22][23][24][25][26][27][28][29][30][31][32] (see also [33] for a pedagogical introduction on the subject). Thus, the details of the reheating process between T max and T RH become important.…”