Looking for the Sunyaev-Zeldovich Effect toward Distant ROSAT Clusters of Galaxies*

We report on observations of the Sunyaev-Zeldovich effect toward X-ray ROSAT clusters taken with a double-channel (1.2 and 2 mm) photometer installed at the focus of the 15 m Swedish ESO Submillimeter Telescope antenna in Chile. This paper describes the first results obtained for the high-z clusters S1077, A2744, and S295. Marginal detections were found for A2744, and at 1 mm for S1077. We discuss these data in terms of contamination of sources along the line of sight and give a constraint on the amplitude of the kinematic effect.