Photometric observations of galaxy clusters from a new X-ray survey

We present the first results of our photometric observations of galaxy clus ters from a new ROSAT X-ray survey of clusters. The observations were begun in the fall of 2000 with the 1.5-m telescope (AZT-22) that recently became operational at TUBITAK National Observatory (Turkey). The first series of observations was carried out in September-November 2000. Magnitudes of the brightest galaxies were measured for seven clusters, and photometric estima tes of their redshifts were obtained. These first observations show that th e necessary photometry for most galaxy clusters from the X-ray survey can b e performed even during this year. (C) 2001 MAIK "Nauka/Interperiodica".