Multicolor photometry of the galaxies in the central region of Abell 2634

An optical photometric observation with the Beijing-Arizona-Taipei-Connecti cut multicolor system is carried out for the central region of the nearby c luster of galaxies Abell 2634. From the 2K x 2K CCD images with 14 filters, which cover a range of wavelength from 3600 to 10000 Angstrom, 5572 source s are AZ, detected down to V similar to 20 mag in a field of 56' x 56' cent ered on this regular cluster of galaxies. As a result, we achieved the spec tral energy distributions (SEDs) of all sources detected. There are 178 pre viously known galaxies included in our observations, 147 of which have know n radial velocities in the literature. After excluding the foreground and b ackground galaxies, a sample of 124 known members is formed for an investig ation of the SED properties. The comparison of observed SEDs of the early-t ype member galaxies with the template SEDs demonstrates the accuracy and re liability of our photometric measurements. Based on the knowledge of SED pr operties of member galaxies, we performed the selection of faint galaxies b elonging to Abell 2634. It is well shown that the color-color diagrams are powerful in the star-galaxy separation. As a result, 359 faint galaxies are selected by their color features. The technique of photometric redshift an d color-magnitude correlation for the early-type galaxies are applied for t hese faint galaxies, and a list of 74 faint member galaxies is achieved. On the basis of the newly generated sample of member galaxies, the spatial di stribution and color-magnitude relation of the galaxies in the core region of Abell 2634 are discussed. There exists a tendency that the color index d ispersion of the early-type members is larger for the outer region, which m ight reflect some clues about the environmental effect on the evolution of galaxies in a cluster.