Gravitational Wave Background and Non-Gaussianity as a Probe of the Curvaton Scenario

TL;DR

This paper explores how gravitational wave background and non-Gaussian features in scalar perturbations can jointly probe the curvaton mechanism, providing complementary observational constraints beyond current capabilities.

Contribution

It demonstrates that gravitational waves and non-Gaussianity measurements can together determine curvaton properties, even if non-Gaussianity is not detected by Planck.

Findings

Future space-based interferometers can constrain curvaton parameters.

Gravitational wave background and non-Gaussianity offer complementary insights.

Even non-detections by Planck can be complemented by future observations.

Abstract

We study observational implications of the stochastic gravitational wave background and a non-Gaussian feature of scalar perturbations on the curvaton mechanism of the generation of density/curvature fluctuations, and show that they can determine the properties of the curvaton in a complementary manner to each other. Therefore even if Planck could not detect any non-Gaussianity, future space-based laser interferometers such as DECIGO or BBO could practically exhaust its parameter space.