THE COSMOS-WIRCam NEAR-INFRARED IMAGING SURVEY. I. BzK-SELECTED PASSIVE AND STAR-FORMING GALAXY CANDIDATES AT z approx> 1.4

Journal Article · Fri Jan 01 00:00:00 EST 2010 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/708/1/202· OSTI ID:21392494

McCracken, H J; Mellier, Y ^[1]; Capak, P; Salvato, M; Scoville, N Z ^[2]; Aussel, H; Daddi, E ^[3]; Thompson, D ^[4]; Sanders, D B; Ilbert, O ^[5]; Kneib, J -P; Le Fevre, O; Kartaltepe, J ^[6]; Willott, C J ^[7]; Mancini, C; Renzini, A ^[8]; Cook, R ^[9]; Koekemoer, A M ^[10]; Murayama, T; Shioya, Y ^[11]

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1. Institut d'Astrophysique de Paris, UMR7095 CNRS, Universite Pierre et Marie Curie, 98 bis Boulevard Arago, 75014 Paris (France)
2. Spitzer Science Center, 314-6 Caltech, Pasadena, CA 9112 (United States)
3. Service d'Astrophysique, CEA/Saclay, 91191 Gif-sur-Yvette (France)
4. Large Binocular Telescope Observatory, University of Arizona, 933 N. Cherry Ave. Tucson, AZ 85721-0065 (United States)
5. Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States)
6. Laboratoire d'Astrophysique de Marseille, CNRS- Universite d'Aix-Marseille, 38 rue Frederic Joliot-Curie, 13388 Marseille Cedex 13 (France)
7. Herzberg Institute of Astrophysics, National Research Council, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada)
8. INAF, Osservatorio Astronomico Di Padova, Vicolo Osservatorio 2, I-35122, Padova (Italy)
9. Department of Physics, Brown University, Box 1843, Providence, RI 02912 (United States)
10. Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)
11. Research Center for Space and Cosmic Evolution, Ehime University, 2-5 Bunkyo-cho, Matsuyama 790-8577 (Japan)

We present a new near-infrared survey covering the 2 deg{sup 2} COSMOS field conducted using WIRCam at the Canada-France-Hawaii Telescope. By combining our near-infrared data with Subaru B and z images, we construct a deep, wide-field optical-infrared catalog. At K{sub s} < 23 (AB magnitudes), our survey completeness is greater than 90% and 70% for stars and galaxies, respectively, and contains 143,466 galaxies and 13,254 stars. Using the BzK diagram, we divide our galaxy catalog into quiescent and star-forming galaxy candidates. At z approx 2, our catalogs contain 3931 quiescent and 25,757 star-forming galaxies representing the largest and most secure sample at these depths and redshifts to date. Our counts of quiescent galaxies turns over at K{sub s} approx 22, an effect that we demonstrate cannot be due to sample incompleteness. Both the number of faint and bright quiescent objects in our catalogs exceed the predictions of a recent semi-analytic model of galaxy formation, indicating potentially the need for further refinements in the amount of merging and active galactic nucleus feedback at z approx 2 in these models. We measure the angular correlation function for each sample and find that the slope of the field galaxy correlation function flattens to 1.5 by K{sub s} approx 23. At small angular scales, the angular correlation function for passive BzK galaxies is considerably in excess of the clustering of dark matter. We use precise 30-band photometric redshifts to derive the spatial correlation length and the redshift distributions for each object class. At K{sub s} < 22, we find r {sup g}amma{sup /1.8}{sub 0} = 7.0 +- 0.5h {sup -1} Mpc for the passive BzK candidates and 4.7 +- 0.8 h {sup -1} Mpc for the star-forming BzK galaxies. Our pBzK galaxies have an average photometric redshift of z{sub p} approx 1.4, in approximate agreement with the limited spectroscopic information currently available. The stacked K{sub s} image will be made publicly available from IRSA.

• OSTI ID: 21392494
• Journal Information: Astrophysical Journal, Vol. 708, Issue 1; Other Information: DOI: 10.1088/0004-637X/708/1/202; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ANGULAR CORRELATION
APPROXIMATIONS
CORRELATION FUNCTIONS
COSMOLOGY
GALACTIC EVOLUTION
GALAXIES
INFRARED SURVEYS
NONLUMINOUS MATTER
RED SHIFT
STARS
TELESCOPES
UNIVERSE
CALCULATION METHODS
CORRELATIONS
EVOLUTION
FUNCTIONS
GEOLOGIC SURVEYS
GEOPHYSICAL SURVEYS
MATTER