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arXiv · 0905.1552

Non-Gaussianity from Isocurvature Perturbations : Analysis of Trispectrum

Etsuko Kawakami·Masahiro Kawasaki·Kazunori Nakayama·Fuminobu Takahashi
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Abstract

Non-Gaussianity may exist in the CDM isocurvature perturbation. We provide general expressions for the bispectrum and trispectrum of both adiabatic and isocurvature pertubations. We apply our result to the QCD axion case, and found a consistency relation between the coefficients of the bispectrum and trispectrum : tau_{NL}^(iso)~10^3 [f_{NL}^(iso)]^{4/3}, if the axion is dominantly produced by quantum fluctuation. Thus future observations of the trispectrum, as well as the bispectrum, will be important for understanding the origin of the CDM and baryon asymmetry.

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Etsuko Kawakami, Masahiro Kawasaki, Kazunori Nakayama, Fuminobu Takahashi. 2009-05-11. Non-Gaussianity from Isocurvature Perturbations : Analysis of Trispectrum. https://doi.org/10.1088/1475-7516/2009/09/002

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