2006/01/26 by M. Douspis, Marian Douspis, N. Aghanim +3 · 2 citations
Physics and Astronomy · #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Radio Astronomy Observations and Technology #astro-ph
paper · pdf · doi:10.1051/0004-6361:20064915
published as Astron.Astrophys. 456 (2006) 819 · 9 pages
arxiv created 2006/01/26 · openalex publication_date 2006/08/04 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/31
We re-analyse Cosmic Microwave Background data from experiments probing both large and small scales. We assume that measured anisotropies are due not only to primary fluctuations but also, especially at small scales, to secondary effects (namely the Sunyaev-Zel'dovich effect) and possible point source contamination. We first consider primary and secondary anisotropies. For the first time in such analyses, the cosmological dependence of secondary fluctuations is fully taken into account. We show that in that case a higher value of the normalisation is preferred, as found by previous studies, but also higher values of the optical depth τ and power spectrum index ns are needed. In the second part, we include possible contaminations from unresolved and unremoved point sources. We discuss the effects on the cosmological parameters. We further obtain the best combination of relative contributions of the three kinds of sources to the measured microwave power on small scales at each frequency. Our method allows us to simultaneously obtain cosmological parameters and explain the so-called small scale power excess in a consistent way.