Testing Primordial Non-Gaussianity in CMB Anisotropies
| dc.creator | Liguori, M. | |
| dc.creator | Hansen, F. K. | |
| dc.creator | Komatsu, E. | |
| dc.creator | Matarrese, S. | |
| dc.creator | Riotto, A. | |
| dc.date | 2005-09-05 | |
| dc.date | 2005-09-05 | |
| dc.date.accessioned | 2026-07-07T11:24:44Z | |
| dc.date.available | 2026-07-07T11:24:44Z | |
| dc.description | Recent second-order perturbation computations have provided an accurate prediction for the primordial gravitational potential $Φ(x)$ in scenarios in which cosmological perturbations are generated either during or after inflation. This enables us to make realistic predictions for a non-Gaussian part of $Φ(x)$, which is generically written in momentum space as a double convolution of its Gaussian part with a suitable kernel, f_NL(k1,k2). This kernel defines the amplitude and angular structure of the non-Gaussian signals and originates from the evolution of second-order perturbations after the generation of the curvature perturbation. We derive a generic formula for the CMB angular bispectrum with arbitrary f_NL(k1,k2) and examine the detectability of the primordial non-Gaussian signals from various scenarios such as single-field inflation, inhomogeneous reheating, and curvaton scenarios. Our results show that in the standard slow-roll inflation scenario the signal actually comes from the momentum-dependent part of f_NL(k1,k2), and thus it is important to include the momentum dependence in the data analysis. In the other scenarios the primordial non-Gaussianity is comparable to or larger than these post-inflationary effects. We find that WMAP cannot detect non-Gaussian signals generated by these models. Numerical calculations for l>500 are still computationally expensive, and we are not yet able to extend our calculations to Planck's angular resolution; however, there is an encouraging trend which shows that Planck may be able to detect these non-Gaussian signals. | |
| dc.description | 25 pages, 3 figures, 1 table, submitted to Phys. Rev. D | |
| dc.identifier | https://arxiv.org/abs/astro-ph/0509098 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/0509098 | |
| dc.identifier | Phys.Rev.D73:043505,2006 | |
| dc.identifier | doi:10.1103/PhysRevD.73.043505 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/195289 | |
| dc.subject | Astrophysics | |
| dc.title | Testing Primordial Non-Gaussianity in CMB Anisotropies | |
| dc.type | text |