Galaxy evolution in distant, x-ray selected clusters of galaxies, 2: CL 0303+1658 and CL 0303+1717

Abstract

view Abstract Citations (21) References (38) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Galaxy Evolution in Distant, X-Ray Selected Clusters of Galaxies. II. CL 0303+1658 and CL 0303+1717 Fabricant, Daniel G. ; Bautz, Marshall W. ; McClintock, Jeffrey E. Abstract We present a photometric and spectroscopic survey of two clusters of galaxies at z = 0.42. These are members of a sample of five distant, high x-ray luminosity clusters of galaxies, which have been selected from the Einstein Medium Sensitivity Survey Catalog. Our objective is to compare the galaxy population in these x-ray selected clusters to the populations in optically selected clusters, which show strong evolution. We have obtained R and I photometry complete to R ~ 22.3 in a 5.7' x 6.5' field centered on each cluster. In addition, we have obtained the spectra of 69 galaxies in the direction of the two clusters; 53 of these are cluster members. The x-ray luminosities of Cl 0303+1658 and Cl 0302+1717 (0.2-4.5 keV) are ~5 X 10^44^ and ~4 X 10^44^ ergs^-1^, and their velocity dispersions are 921_-123_^+192^ and 821_94_^137^ km s^-1^, respectively. The evolution of the galaxy population observed in optically selected clusters at z ~0.4 (as compared with clusters at the present epoch) is also found in these x-ray selected clusters. This confirms the results that we presented in a previous paper for Cl 1358+6245 at z = 0.33. In both optically and x-ray selected clusters at z ~ 0.4, 20-30% of the galaxies have spectra with strong Balmer absorption lines or emission lines, consistent with recent star formation activity. We identify one possible difference between the optically and x-ray selected clusters; galaxies with very strong Balmer absorption lines, EW <Hdelta_+ Hgamma_>^bar^ > 8 A, are so far absent in our x-ray selected sample, yet they constitute 25% of the spectroscopically active population in Dressler and Gunn's optically selected sample. Publication: The Astronomical Journal Pub Date: January 1994 DOI: 10.1086/116831 Bibcode: 1994AJ....107....8F Keywords: Balmer Series; Emission Spectra; Galactic Clusters; Galactic Evolution; Sky Surveys (Astronomy); Star Formation; X Ray Sources; Absorption Spectra; Astronomical Photometry; Spectrophotometry; Spectrum Analysis; Stellar Luminosity; Astrophysics; X-RAYS: GALAXIES; GALAXIES: CLUSTERS: INDIVIDUAL: CL 0303; 1658; 1717 full text sources ADS | data products SIMBAD (9) NED (2) Related Materials (1) Part 1: 1991ApJ...381...33F