Parametric Decay of the Curvaton

TL;DR

This paper proposes that the curvaton decays through broad parametric resonance, similar to inflaton decay, which could lead to observable gravitational waves without fine-tuning of parameters.

Contribution

It introduces a natural decay mechanism for the curvaton via broad parametric resonance, avoiding the need for tuning couplings, and explores potential observable signatures.

Findings

Curvaton decay can occur through broad parametric resonance.

This decay mechanism does not require tuning of coupling constants.

Potential for observable gravitational waves at low inflation scales.

Abstract

We argue that the curvaton decay takes place most naturally by way of a broad parametric resonance. The mechanism is analogous to resonant inflaton decay but does not require any tuning of the curvaton coupling strength to other scalar fields. For low scale inflation and a correspondingly low mass scale for the curvaton, we speculate on observable consequences including the possibility of stochastic gravitational waves