Strongly scale-dependent polyspectra from curvaton self-interactions
Abstract
We study the scale dependence of the non-linearity parameters f_NL and g_NL in curvaton models with self-interactions. We show that the spectral indices n_fNL=d ln|f_NL|/(d ln k) and n_gNL=d ln |g_NL|/(d ln k) can take values much greater than the slow--roll parameters and the spectral index of the power spectrum. This means that the scale--dependence of the bi and trispectrum could be easily observable in this scenario with Planck, which would lead to tight additional constraints on the model. Inspite of the highly non-trivial behaviour of f_NL and g_NL in the curvaton models with self-interactions, we find that the model can be falsified if g_NL(k) is also observed.
Cite
@article{arxiv.1108.2708,
title = {Strongly scale-dependent polyspectra from curvaton self-interactions},
author = {Christian T. Byrnes and Kari Enqvist and Sami Nurmi and Tomo Takahashi},
journal= {arXiv preprint arXiv:1108.2708},
year = {2015}
}
Comments
19 pages, many figures. v2: Figure 4 replaced with a corrected normalisation, conclusions unchanged. Matches version published in JCAP