In order to assess the potential of future microwave anisotropy space experiments for detecting clusters by their Sunyaev-Zeldovich ( SZ ) thermal effect , we have simulated maps of the large scale distribution of their Compton parameter y and of the temperature anisotropy \Delta T / T induced by their proper motion .
Our model is based on a predicted distribution of clusters per unit redshift and flux density using a Press-Schecter approach ( De Luca et al .
1995 ) .

These maps were used to create simulated microwave sky by adding them to the microwave contributions of the emissions of our Galaxy ( free-free , dust and synchrotron ) and the primary Cosmic Microwave Background ( CMB ) anisotropies ( corresponding to a COBE-normalized standard Cold Dark Model scenario ) .
In order to simulate measurements representative of what current technology should achieve , “ observations ” were performed according to the instrumental characteristics ( number of spectral bands , angular resolutions and detector sensitivity ) of the COBRAS/SAMBA space mission .
These observations were separated into physical components by an extension of the Wiener filtering theory ( Bouchet et al .
1996 ) .
We then analyzed the resulting y and \Delta T / T maps which now include both the primary anisotropies and those superimposed due to cluster motions .
A cluster list was obtained from the recovered y maps , and their profiles compared with the input ones .
Even for low y -values , the input and output profiles show good agreement , most notably in the outer parts of the profile where values as low as y \simeq 3. 10 ^ { -7 } are properly mapped .
We also construct and optimize a spatial filter which is used to derive the accuracy on the measurement of the radial peculiar velocity of a detected cluster .
We derive the accuracy of the mapping of the very large scale cosmic velocity field obtained from such measurements .