1996/07/05 by Domingos Barbosa, Barbosa, Domingos, James G. Bartlett +5
Physics and Astronomy · #Astrophysics (astro-ph) #FOS: Physical sciences #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/9607036
6 pages, postscript file. Proceedings of the 21 Rencontres de Moriond "Microwave Background Anisotropies", Les Arcs, France
arxiv created 1996/07/05 · arxiv updated 2016/08/30
We examine how the Sunyaev-Zel'dovich (SZ) effect of clusters can probe Ωo. Using self-consistent models of X-ray clusters in the context of hierarchical models of structure formation, we show that both the mean Compton \it y parameter and the number of clusters observed via the SZ effect strongly depend on Ωo. These quantities are higher in open cosmological models due to the earlier epoch of structure formation. Specifically, we compare two models which are able to reproduce the present abundance of X-ray clusters, one for Ωo=0.2 and the other Ω= 1. For Ωo=0.2, \ymean exceeds the current FIRAS limit of 1.5×10-5. Also, the SZ redshift source distribution considerably differs in the two cosmological models. Thus, these results show that both an improvement in our knowledge of CMB spectral distortions and the realization of millimeter surveys to look for SZ sources over a large area of the sky should produce interesting constraints on Ωo and on the evolution of the baryonic fractionof virialized structures.