1108.2708 (Christian T. Byrnes et al.)

Strongly scale-dependent polyspectra from curvaton self-interactions    [PDF]

Christian T. Byrnes, Kari Enqvist, Sami Nurmi, Tomo Takahashi

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.

View original: http://arxiv.org/abs/1108.2708