Enhanced (p)reheating in DBI Inflation

TL;DR

This paper investigates the process of preheating in DBI hybrid inflation, demonstrating that even with small couplings, narrow parametric resonance efficiently converts inflaton energy into matter fields, leading to reheating.

Contribution

It provides a detailed analysis of preheating dynamics in DBI inflation, highlighting the efficiency of narrow parametric resonance despite weak couplings.

Findings

Preheating occurs via narrow parametric resonance.

The process efficiently produces matter fields at late times.

Reheating temperature is estimated from inflaton decay.

Abstract

We study preheating in DBI hybrid inflation. Preheating occurs since the matter fields are non-minimally coupled to the inflaton. Despite the coupling being small, preheating happens as a narrow parametric resonance in which matter fields and inflaton modes are exponentially created. We show that, within the approximations used, the process is very efficient at late times. The resonance stage gives way to the decay of the inflaton into bosonic or fermionic degrees of freedom and the corresponding reheating temperature is determined.