GALAXIES IN X-RAY GROUPS. I. ROBUST MEMBERSHIP ASSIGNMENT AND THE IMPACT OF GROUP ENVIRONMENTS ON QUENCHING
- Department of Astronomy, University of California, Berkeley, CA 94720 (United States)
- Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States)
- Max-Planck-Institut fuer Extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching (Germany)
- Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States)
- Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa, Chiba 277-8568 (Japan)
- Bureau des Galaxies, Etoiles, Physique, Instrumentation (GEPI), University of Paris Denis Diderot, F-75205 Paris Cedex 13 (France)
- Laboratoire d'Astrophysique de Marseille, CNRS Universite de Provence, 38 rue F. Joliot-Curie, F-13388 Marseille Cedex 13 (France)
- Service d'Astrophysique, CEA-Saclay, Orme de Merisiers, Bat. 709, F-91191 Gif-sur-Yvette (France)
- Kavli Institute for Particle Astrophysics and Cosmology, Stanford, CA 94305 (United States)
- Spitzer Science Center, 314-6 Caltech, 1201 East California Boulevard, Pasadena, CA 91125 (United States)
- European Southern Observatory, Karl-Schwarzchild-strasse 2, D-85748 Garching (Germany)
- Universita di Napolia Federico II, Dipartimento di Sciennze Fisiche and INAF Observatorio Astronomico di Capodimonte, v. Moiariello 16, I-80131 Napoli (Italy)
- Laboratoire d'Astrophysique, Ecole Polytechnique Federale de Lausanne (EPFL), Observatoire de Sauverny, CH-1290 Versoix (Switzerland)
Understanding the mechanisms that lead dense environments to host galaxies with redder colors, more spheroidal morphologies, and lower star formation rates than field populations remains an important problem. As most candidate processes ultimately depend on host halo mass, accurate characterizations of the local environment, ideally tied to halo mass estimates and spanning a range in halo mass and redshift, are needed. In this work, we present and test a rigorous, probabilistic method for assigning galaxies to groups based on precise photometric redshifts and X-ray-selected groups drawn from the COSMOS field. The groups have masses in the range 10{sup 13} {approx}< M{sub 200c}/M{sub Sun} {approx}< 10{sup 14} and span redshifts 0 < z < 1. We characterize our selection algorithm via tests on spectroscopic subsamples, including new data obtained at the Very Large Telescope, and by applying our method to detailed mock catalogs. We find that our group member galaxy sample has a purity of 84% and completeness of 92% within 0.5 R{sub 200c}. We measure the impact of uncertainties in redshifts and group centering on the quality of the member selection with simulations based on current data as well as future imaging and spectroscopic surveys. As a first application of our new group member catalog which will be made publicly available, we show that member galaxies exhibit a higher quenched fraction compared to the field at fixed stellar mass out to z {approx} 1, indicating a significant relationship between star formation and environment at group scales. We also address the suggestion that dusty star-forming galaxies in such groups may impact the high-l power spectrum of the cosmic microwave background and find that such a population cannot explain the low power seen in recent Sunyaev-Zel'dovich measurements.
- OSTI ID:
- 22004597
- Journal Information:
- Astrophysical Journal, Vol. 742, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
- Country of Publication:
- United States
- Language:
- English
Similar Records
THE CORRELATED FORMATION HISTORIES OF MASSIVE GALAXIES AND THEIR DARK MATTER HALOS
GALAXY CLUSTERS IN THE LINE OF SIGHT TO BACKGROUND QUASARS. III. MULTI-OBJECT SPECTROSCOPY