Shape of high order correlation functions in CMB anisotropy maps
Abstract
We present a phenomenological investigation of nonGaussian effects that could be seen on CMB temperature maps. Explicit expressions for the temperature correlation functions are given for different types of primordial mode couplings. We argue that a simplified description of the radial transfer function for the temperature anisotropies allows one to get insights into the general properties of the bispectrum and trispectrum. The accuracy of these results is explored together with the use of the small scale approximation to get explicit expressions of high order spectra. The bispectrum is found to have alternate signs for the successive acoustic peaks. Sign patterns for the trispectrum are more complicated and depend specifically on the type of metric couplings. Local primordial couplings are found to give patterns that are different from those expected from weak lensing effects.
 Authors:
 Service de Physique Theorique, CEA/DSM/SPhT, Unite de Recherche Associee au CNRS, CEA/Saclay 91191 GifsurYvette Cedex (France)
 Publication Date:
 OSTI Identifier:
 20782895
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 8; Other Information: DOI: 10.1103/PhysRevD.73.083524; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ANISOTROPY; APPROXIMATIONS; CORRELATION FUNCTIONS; COSMIC RADIATION; COSMOLOGY; ENERGY SPECTRA; RADIOWAVE RADIATION; TRANSFER FUNCTIONS
Citation Formats
Brunier, Tristan, and Bernardeau, Francis. Shape of high order correlation functions in CMB anisotropy maps. United States: N. p., 2006.
Web. doi:10.1103/PHYSREVD.73.083524.
Brunier, Tristan, & Bernardeau, Francis. Shape of high order correlation functions in CMB anisotropy maps. United States. doi:10.1103/PHYSREVD.73.083524.
Brunier, Tristan, and Bernardeau, Francis. Sat .
"Shape of high order correlation functions in CMB anisotropy maps". United States.
doi:10.1103/PHYSREVD.73.083524.
@article{osti_20782895,
title = {Shape of high order correlation functions in CMB anisotropy maps},
author = {Brunier, Tristan and Bernardeau, Francis},
abstractNote = {We present a phenomenological investigation of nonGaussian effects that could be seen on CMB temperature maps. Explicit expressions for the temperature correlation functions are given for different types of primordial mode couplings. We argue that a simplified description of the radial transfer function for the temperature anisotropies allows one to get insights into the general properties of the bispectrum and trispectrum. The accuracy of these results is explored together with the use of the small scale approximation to get explicit expressions of high order spectra. The bispectrum is found to have alternate signs for the successive acoustic peaks. Sign patterns for the trispectrum are more complicated and depend specifically on the type of metric couplings. Local primordial couplings are found to give patterns that are different from those expected from weak lensing effects.},
doi = {10.1103/PHYSREVD.73.083524},
journal = {Physical Review. D, Particles Fields},
number = 8,
volume = 73,
place = {United States},
year = {Sat Apr 15 00:00:00 EDT 2006},
month = {Sat Apr 15 00:00:00 EDT 2006}
}

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