2001/10/18 by Asantha Cooray · 1 citation
Physics and Astronomy · #Anisotropy #Astrophysics #COSMIC cancer database #Computational physics #Cosmic microwave background #Cosmic variance #Cosmology and Gravitation Theories #Covariance #Galaxies: Formation, Evolution, Phenomena #Galaxy #Gravitational lens #Multipole expansion #Non-Gaussianity #Optics #Physics #Quantum mechanics #Radio Astronomy Observations and Technology #Spectral density #Statistics #Strong gravitational lensing #Trispectrum #Weak gravitational lensing #astro-ph
paper · pdf · doi:10.1103/physrevd.65.063512
published as Phys.Rev. D65 (2002) 063512 · 10 pages, 5 figures; submitted to Phys. Rev. D
arxiv created 2001/10/18 · openalex publication_date 2002/02/28 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We discuss the non-Gaussian contribution to the power spectrum covariance of cosmic microwave background (CMB) anisotropies resulting through weak gravitational lensing angular deflections and the correlation of deflections with secondary sources of temperature fluctuations generated by the large scale structure, such as the integrated Sachs-Wolfe effect and the Sunyaev-Zel'dovich effect. This additional contribution to the covariance of binned angular power spectrum, beyond the well known cosmic variance and any associated instrumental noise, results from a trispectrum, or a four point correlation function, in temperature anisotropy data. With substantially wide bins in multipole space, the resulting non-Gaussian contribution from lensing to the binned power spectrum variance is insignificant out to multipoles of a few thousand and is not likely to affect the cosmological parameter estimation with acoustic peaks and the damping tail. The non-Gaussian contribution to covariance, however, should be considered when interpreting binned CMB power spectrum measurements at multipoles of a few thousand corresponding to angular scales of few arcminutes and less.