The Sunyaev-Zeldovich MITO Project

Compton scattering of the cosmic microwave background radiation by electrons in the hot gas in clusters of galaxies - the Sunyaev-Zeldovich effect - has long been recognized as a uniquely important feature, rich in cosmological and astrophysical information. We briefly describe the effect, and emphasize the need for detailed S-Z and X-ray measurements of nearby clusters in order to use the effect as a precise cosmological probe. This is the goal of the MITO project, whose first stage consisted of observations of the S-Z effect in the Coma cluster. We report the results of these observations.Comment: To appear in Proceedings of `Understanding our Universe at the close of XXth century', School held Apr 25 - May 6 2000, Cargese, 16 pages LaTeX, 2 figures ps (using elsart.sty & elsart.cls), text minor revisio

Search for the Sunyaev-Zeldovich effect in the coma cluster with the MITO experiment

We report the strategy for observing the Sunyaev-Zeldovich effect towards the Coma cluster of galaxies with the MITO telescope. The instrument has a 17 arcminutes FWHM field of View and uses a 3-field square wave mechanical modulation with a beamthrow of 41 arcminutes. The channels centered at 2.1, 1.4, 1.1 and 0.85 mm allow for matching the Sunyaev-Zeldovich effect spectral range and monitoring atmospheric fluctuations for spectral decorrelation. in this paper we describe both the analysis procedure and the preliminary results of our observations. We also make a first comparison with the available X-ray data

The Sunyaev-Zeldovich effect and the MITO experiment, a project for cosmological parameters determination

Compton scattering of the cosmic microwave background radiation by electrons in the hot gas in clusters of galaxies - the Sunyaev-Zeldovich effect - has long been recognized as a uniquely important feature, rich in cosmological and astrophysical information. Here, we briefly report a theoretical description of this effect. Moreover we discuss the importance to have high-quality clusters X-maps in order to yield an accurate value of the Hubble constant and of other cosmological parameters, strongly preferring nearby clusters observations. Finally we present the MITO experiment, devoted to the observation of the richest nearby cluster, the Coma cluster (A1656)