Non-Gaussianity from Features

Abstract

The strongest non-Gaussianity in single-scalar potential models of inflation is associated with features in the power spectrum. We stress the importance of accurately modelling the expected signal in order for the standard estimator to minimize contamination by random noise. We present explicit formulae which improve on the approximation introduced by Adshead, Hu, Dvorkin and Peiris. We also compare with a simple, analytic model of the first feature, and quantify our results using the correlators of Hung, Fergusson and Shellard.