Hunting for Isocurvature Modes in the CMB non-Gaussianities

D. Langlois 1 Bartjan Van Tent 2
1 APC - THEORIE
IAP - Institut d'Astrophysique de Paris, APC - UMR 7164 - AstroParticule et Cosmologie
Abstract : We investigate new shapes of local primordial non-Gaussianities in the CMB. Allowing for a primordial isocurvature mode along with the main adiabatic one, the angular bispectrum is in general a superposition of six distinct shapes: the usual adiabatic term, a purely isocurvature component and four additional components that arise from correlations between the adiabatic and isocurvature modes. We present a class of early Universe models in which various hierarchies between these six components can be obtained, while satisfying the present upper bound on the isocurvature fraction in the power spectrum. Remarkably, even with this constraint, detectable non-Gaussianity could be produced by isocurvature modes. We finally discuss the prospects of detecting these new shapes with the Planck satellite.
Document type :
Journal articles
Classical and Quantum Gravity, Institute of Physics: Hybrid Open Access, 2011, 28 (22), pp.222001. <10.1088/0264-9381/28/22/222001>


https://hal.archives-ouvertes.fr/hal-00589058
Contributor : Patricia Dubois-Violette <>
Submitted on : Wednesday, April 27, 2011 - 12:56:59 PM
Last modification on : Thursday, April 23, 2015 - 2:11:32 PM

Identifiers

Collections

APC | CEA | INSU | OBSPM | UPMC | IAP | ENCYCLO_1 | UGA

Citation

D. Langlois, Bartjan Van Tent. Hunting for Isocurvature Modes in the CMB non-Gaussianities. Classical and Quantum Gravity, Institute of Physics: Hybrid Open Access, 2011, 28 (22), pp.222001. <10.1088/0264-9381/28/22/222001>. <hal-00589058>

Export

Share

Metrics

Consultation de la notice

1