Extremely Red Objects in the Field of QSO 1213-0017: A Galaxy Concentration at z=1.31

Abstract

We have discovered a concentration of extremely red objects (EROs; R-K>6) in the field of the z=2.69 quasar QSO 1213-0017 (UM 485), which is significantly overabundant compared to the field ERO surface density. The optical/near-IR colors of the EROs and numerous other red galaxies in this field are consistent with elliptical galaxies at z=1-2. HST optical images for a subset of galaxies show regular morphologies, most of them being disky or diffuse and without any obvious evidence for interactions. Ground-based IR images show similar morphologies, indicating any dust reddening in these objects is spatially uniform. Optical spectroscopy with the W. M. Keck Telescope has found that four of the red galaxies lie at <z>=1.31, and a fifth lies in the foreground at z=1.20. Of the <z>=1.31 galaxies, one is a reddened AGN while the remaining three have rest-frame UV absorption-line spectra characteristic of old (few Gyr) stellar populations, similar to the old red galaxy LBDS 53W091 at z=1.55. Including the MgII absorber seen in the QSO spectrum, we find five galaxies at <z>=1.31 spread over 1.5 h_50^{-1} Mpc on the sky. These results suggest we have discovered a coherent structure of old galaxies at high-redshift, possibly associated with a massive galaxy cluster.

37 pages including 11 Postscript figures. To appear in the June 2000 issue of the Astronomical Journal

References in corpus (8)

• Far-Ultraviolet Radiation from Elliptical Galaxies
• The Discovery of ERO Counterparts to Faint Submm Galaxies
• An X-ray Selected Galaxy Cluster at z=1.26
• Hubble Space Telescope Imaging of the CFRS and LDSS Redshift Surveys---III. Field elliptical galaxies at 0.2 < z < 1.0
• The Surface Density of Extremely Red Objects
• Galaxy number counts- IV. surveying the Herschel deep field in the near-infrared
• On The Age Estimation of LBDS 53W091
• Near Infrared Observations of the Extremely Red Object CL0939+4713B: An Old Galaxy at z~1.58?

Cited by in corpus (30)

• An excess of submm sources near 4C41.17: a candidate proto-cluster at z=3.8?
• The Las Campanas IR Survey: Early Type Galaxy Progenitors Beyond Redshift One
• The Las Campanas IR Survey. II. Photometric redshifts, comparison with models and clustering evolution
• High-Redshift Superwinds as the Source of the Strongest Mg II Absorbers: A Feasibility Analysis
• Morphologies and Color Gradients of Luminous Evolved Galaxies at z~1.5
• A Hubble Space Telescope Lensing Survey of X-ray Luminous Galaxy Clusters: II. A Search for Gravitationally Lensed EROs
• The Spatial Clustering of Distant, z~1, Early-Type Galaxies
• HST/WFPC2 Morphologies of K-selected Extremely Red Galaxies
• The rest-frame $K$-band luminosity function of galaxies in clusters to $z=1.3$
• Extremely red galaxy counterparts to 7C radio sources
• Red Galaxy Clustering in the NOAO Deep Wide-Field Survey
• Understanding the nature of the optically faint radio sources and their connection to the submillimeter population
• A Disk Galaxy of Old Stars at z ~ 2.5
• The relative abundances of ellipticals and starbursts among the Extremely Red Galaxies
• Optical and Near-Infrared Spectroscopy of a High-Redshift, Hard X-ray Emitting Spiral Galaxy
• Overdensities of Extremely Red Objects in the Fields of High-Redshift Radio-Loud Quasars
• Spectroscopic Confirmation of a Radio-Selected Galaxy Overdensity at z=1.11
• Very Red and Extremely Red Galaxies in the Fields of z ~ 1.5 Radio-Loud Quasars
• The density of extremely red objects around high-z radio-loud AGN
• Search for sub-mm, mm and radio continuum emission from Extremely Red Objects
• Radio galaxy selected clusters at high redshift and associated ERO overdensities
• The first ISO ERO: a dusty quasar at z = 1.5
• Tunable-filter imaging of quasar fields at z~1. I. A cluster around MRC B0450-221
• Stellar Populations of Luminous Evolved Galaxies at z~1.5
• Extremely Red Objects in Two Quasar Fields at z ~ 1.5
• B3 0003+387: AGN Marked Large-Scale Structure at z=1.47?
• Number Density Evolution of Ks -band Selected High Redshift Galaxy Populations in the AKARI North Ecliptic Pole Field
• Morphologies in a Cluster of Extremely Red Galaxies with Old Stellar Populations at z=1.34
• A massive disk galaxy at z>3 along the sightline of QSO 1508+5714
• The spatial clustering of radio sources in NVSS and FIRST; implications for galaxy clustering evolution