GALAXY CLUSTERING IN THE COMPLETED SDSS REDSHIFT SURVEY: THE DEPENDENCE ON COLOR AND LUMINOSITY

Journal Article · Wed Jul 20 04:00:00 EDT 2011 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/736/1/59· OSTI ID:21578302

Zehavi, Idit ^[1]; Zheng, Zheng ^[2]; Weinberg, David H ^[3]; Blanton, Michael R ^[4]; Bahcall, Neta A; Gunn, James E; Lupton, Robert H; Strauss, Michael A ^[5]; Berlind, Andreas A ^[6]; Brinkmann, Jon ^[7]; Frieman, Joshua A ^[8]; Nichol, Robert C; Percival, Will J ^[9]; Schneider, Donald P ^[10]; Skibba, Ramin A ^[11]; Tegmark, Max ^[12]; York, Donald G ^[13]

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1. Department of Astronomy and CERCA, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106 (United States)
2. Yale Center for Astronomy and Astrophysics, Yale University, New Haven, CT 06520 (United States)
3. Department of Astronomy and CCAPP, Ohio State University, Columbus, OH 43210 (United States)
4. Center for Cosmology and Particle Physics, Department of Physics, New York University, New York, NY 10003 (United States)
5. Department of Astrophysical Sciences, Princeton University, Peyton Hall, Princeton, NJ 08540 (United States)
6. Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235 (United States)
7. Apache Point Observatory, P.O. Box 59, Sunspot, NM 88349 (United States)
8. Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL 60510 (United States)
9. Institute of Cosmology and Gravitation, University of Portsmouth, Portsmouth P01 2EG (United Kingdom)
10. Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States)
11. Steward Observatory, University of Arizona, 933 N. Cherry Avenue, Tucson, AZ 85121 (United States)
12. Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)
13. Department of Astronomy and Astrophysics, The University of Chicago, 5640 S. Ellis Avenue, Chicago, IL 60615 (United States)

We measure the luminosity and color dependence of galaxy clustering in the largest-ever galaxy redshift survey, the main galaxy sample of the Sloan Digital Sky Survey Seventh Data Release. We focus on the projected correlation function w{sub p} (r{sub p}) of volume-limited samples, extracted from the parent sample of {approx}700,000 galaxies over 8000 deg{sup 2}, extending up to redshift of 0.25. We interpret our measurements using halo occupation distribution (HOD) modeling assuming a {Lambda}CDM cosmology (inflationary cold dark matter with a cosmological constant). The amplitude of w{sub p} (r{sub p}) grows slowly with luminosity for L < L{sub *} and increases sharply at higher luminosities, with a large-scale bias factor b(> L) x ({sigma}{sub 8}/0.8) = 1.06 + 0.21(L/L{sub *}){sup 1.12}, where L is the sample luminosity threshold. At fixed luminosity, redder galaxies exhibit a higher amplitude and steeper correlation function, a steady trend that runs through the 'blue cloud' and 'green valley' and continues across the 'red sequence'. The cross-correlation of red and blue galaxies is close to the geometric mean of their autocorrelations, dropping slightly below at r{sub p} < 1 h{sup -1} Mpc. The luminosity trends for the red and blue galaxy populations separately are strikingly different. Blue galaxies show a slow but steady increase of clustering strength with luminosity, with nearly constant shape of w{sub p} (r{sub p}). The large-scale clustering of red galaxies shows little luminosity dependence until a sharp increase at L > 4 L{sub *}, but the lowest luminosity red galaxies (0.04-0.25 L{sub *}) show very strong clustering on small scales (r{sub p} < 2 h{sup -1} Mpc). Most of the observed trends can be naturally understood within the {Lambda}CDM+HOD framework. The growth of w{sub p} (r{sub p}) for higher luminosity galaxies reflects an overall shift in the mass scale of their host dark matter halos, in particular an increase in the minimum host halo mass M{sub min}. The mass at which a halo has, on average, one satellite galaxy brighter than L is M{sub 1} {approx} 17 M{sub min}(L) over most of the luminosity range, with a smaller ratio above L{sub *}. The growth and steepening of w{sub p} (r{sub p}) for redder galaxies reflects the increasing fraction of galaxies that are satellite systems in high-mass halos instead of central systems in low-mass halos, a trend that is especially marked at low luminosities. Our extensive measurements, provided in tabular form, will allow detailed tests of theoretical models of galaxy formation, a firm grounding of semiempirical models of the galaxy population, and new constraints on cosmological parameters from combining real-space galaxy clustering with mass-sensitive statistics such as redshift-space distortions, cluster mass-to-light ratios, and galaxy-galaxy lensing.

• OSTI ID: 21578302
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 736; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
COLOR
CORRELATION FUNCTIONS
DISTANCE
FUNCTIONS
GALAXIES
GALAXY CLUSTERS
LUMINOSITY
OPTICAL PROPERTIES
ORGANOLEPTIC PROPERTIES
PHYSICAL PROPERTIES
RED SHIFT
SIMULATION