Non-Gaussianity from isocurvature perturbations

Journal Article · Sat Nov 15 00:00:00 EST 2008 · Journal of Cosmology and Astroparticle Physics

DOI:https://doi.org/10.1088/1475-7516/2008/11/019· OSTI ID:22156825

Kawasaki, Masahiro; Nakayama, Kazunori; Sekiguchi, Toyokazu; Suyama, Teruaki ^[1]; Takahashi, Fuminobu ^[2]

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1. Institute for Cosmic Ray Research, University of Tokyo, Kashiwa 277-8582 (Japan)
2. Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa 277-8568 (Japan)

We develop a formalism for studying 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 cosmic microwave background 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 quantum chromodynamics axion and show that it can actually induce sizable non-Gaussianity for the inflationary scale, H{sub inf} = O(10{sup 9}-10{sup 11}) GeV.

• OSTI ID: 22156825
• Journal Information: Journal of Cosmology and Astroparticle Physics, Vol. 2008, Issue 11; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 1475-7516
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
DISTURBANCES
FLUCTUATIONS
GEV RANGE
NONLUMINOUS MATTER
PHOTONS
QUANTUM CHROMODYNAMICS
RELICT RADIATION
TEMPERATURE DEPENDENCE