STELLAR AND TOTAL BARYON MASS FRACTIONS IN GROUPS AND CLUSTERS SINCE REDSHIFT 1

Journal Article · Sun Sep 20 00:00:00 EDT 2009 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/703/1/982· OSTI ID:21371946

Giodini, S; Pierini, D; Finoguenov, A; Pratt, G W; Boehringer, H ^[1]; Leauthaud, A ^[2]; Guzzo, L ^[3]; Aussel, H ^[4]; Bolzonella, M ^[5]; Capak, P ^[6]; Elvis, M ^[7]; Hasinger, G ^[8]; Ilbert, O; Kartaltepe, J S ^[9]; Koekemoer, A M ^[10]; Lilly, S J ^[11]; Massey, R; Rhodes, J; Salvato, M ^[12]; McCracken, H J ^[13]

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1. Max Planck Institut fuer Extraterrestrische Physik, Giessenbachstrasse, Garching bei Muenchen D-85748 (Germany)
2. LBNL and Berkeley Center for Cosmological Physics, University of California, Berkeley, CA 94720 (United States)
3. INAF-Osservatorio Astronomico di Brera, Via Bianchi 46, I-23807 Merate (Saint Lucia) (Italy)
4. AIM Unite Mixte de Recherche CEA CNRS, Universite Paris VII UMR n158, Paris (France)
5. INAF-Bologna Astronomical Observatory, via Ranzani 1, I-40127 Bologna (Italy)
6. Spitzer Science Center, 314-6 Caltech, Pasadena, CA 91125 (United States)
7. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)
8. Max-Planck-Institut fuer Plasmaphysik, Boltzmannstrasse 2, Garching bei Muenchen D-85748 (Germany)
9. Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States)
10. Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)
11. Institute of Astronomy, Department of Physics, Eidgenoessische Technische Hochschule, ETH Zurich, CH-8093 (Switzerland)
12. California Institute of Technology, MC 105-24, 1200 East California Boulevard, Pasadena, CA 91125 (United States)
13. Institut d'Astrophysique de Paris, UMR 7095 CNRS, Universite Pierre et Marie Curie, 98bis boulevard Arago, 75014 Paris (France)

We investigate if the discrepancy between estimates of the total baryon mass fraction obtained from observations of the cosmic microwave background (CMB) and of galaxy groups/clusters persists when a large sample of groups is considered. To this purpose, 91 candidate X-ray groups/poor clusters at redshift 0.1 <= z <= 1 are selected from the COSMOS 2 deg{sup 2} survey, based only on their X-ray luminosity and extent. This sample is complemented by 27 nearby clusters with a robust, analogous determination of the total and stellar mass inside R {sub 500}. The total sample of 118 groups and clusters with z <= 1 spans a range in M {sub 500} of {approx}10{sup 13}-10{sup 15} M {sub sun}. We find that the stellar mass fraction associated with galaxies at R {sub 500} decreases with increasing total mass as M {sup -0.37+}-{sup 0.04} {sub 500}, independent of redshift. Estimating the total gas mass fraction from a recently derived, high-quality scaling relation, the total baryon mass fraction (f {sup stars+gas} {sub 500} = f {sup stars} {sub 500} + f {sup gas} {sub 500}) is found to increase by {approx}25%, when M{sub 500} increases from (M) = 5 x 10{sup 13} M{sub sun} to (M) = 7 x 10{sup 14} M{sub sun}. After consideration of a plausible contribution due to intracluster light (11%-22% of the total stellar mass) and gas depletion through the hierarchical assembly process (10% of the gas mass), the estimated values of the total baryon mass fraction are still lower than the latest CMB measure of the same quantity (WMAP5), at a significance level of 3.3sigma for groups of (M) = 5 x 10{sup 13} M{sub sun}. The discrepancy decreases toward higher total masses, such that it is 1sigma at (M) = 7 x 10{sup 14} M{sub sun}. We discuss this result in terms of nongravitational processes such as feedback and filamentary heating.

• OSTI ID: 21371946
• Journal Information: Astrophysical Journal, Vol. 703, Issue 1; Other Information: DOI: 10.1088/0004-637X/703/1/982; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
BARYONS
COSMOLOGY
GALAXY CLUSTERS
LUMINOSITY
MASS
RED SHIFT
RELICT RADIATION
UNIVERSE
X-RAY GALAXIES
COSMIC RAY SOURCES
COSMIC X-RAY SOURCES
ELECTROMAGNETIC RADIATION
ELEMENTARY PARTICLES
FERMIONS
GALAXIES
HADRONS
MICROWAVE RADIATION
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
RADIATIONS