Publication : t10/032
The cosmic microwave background bispectrum from the non-linear evolution of the cosmological perturbations
Pitrou C. (Institute of Cosmology & Gravitation, University of Portsmouth, Portsmouth PO1 2EG, England UNITED KINGDOM (UK))Uzan J.-P. (Institut d\'Astrophysique de Paris (IAP-CNRS), 98 bis Bld Arago, F-75014 Paris, FRANCE)
Bernardeau F. (CEA, IPhT (Institut de Physique Théorique), F-91191 Gif-sur-Yvette, France)
Abstract:Année de publication : 2010
This article presents the first computation of the complete bispectrum of the cosmic microwave background temperature anisotropies arising from the evolution of all cosmic fluids up to second order, including neutrinos. Gravitational couplings, electron density fluctuations and the second order Boltzmann equation are fully taken into account. Comparison to limiting cases that appeared previously in the literature are provided. These are regimes for which analytical insights can be given. The final results are expressed in terms of equivalent fNL for different configurations. It is found that for moments up to lmax=2000, the signal generated by non-linear effects is equivalent to fNL~5 for both local-type and equilateral-type primordial non-Gaussianity.
Revue : JCAP 1007 003 (2010)
DOI : 10.1088/1475-7516/2010/07/003
Preprint : arXiv:1003.0481
PACS : 98.80.-k
Langue : Anglais
Fichier(s) à télécharger :
1475-7516_2010_07_003.pdf publi.pdf
