Non-Gaussianity from isocurvature perturbations
Astrophysics
2014-11-18 v3 General Relativity and Quantum Cosmology
High Energy Physics - Phenomenology
High Energy Physics - Theory
Abstract
We develop a formalism to study non-Gaussianity in both curvature and isocurvature perturbations. It is shown that non-Gaussianity in the isocurvature perturbation between dark matter and photons leaves distinct signatures in the CMB temperature fluctuations, which may be confirmed in future experiments, or possibly, even in the currently available observational data. As an explicit example, we consider the QCD axion and show that it can actually induce sizable non-Gaussianity for the inflationary scale, H_{inf} = O(10^9 - 10^{11})GeV.
Keywords
Cite
@article{arxiv.0808.0009,
title = {Non-Gaussianity from isocurvature perturbations},
author = {Masahiro Kawasaki and Kazunori Nakayama and Toyokazu Sekiguchi and Teruaki Suyama and Fuminobu Takahashi},
journal= {arXiv preprint arXiv:0808.0009},
year = {2014}
}
Comments
24 pages, 6 figures; references added; version to appear in JCAP