Clustering of red galaxies around the z=1.53 quasar 3C270.1

Abstract

In the paradigm of hierarchical galaxy formation, luminous radio galaxies mark mass assembly peaks that should contain clusters of galaxies. Observations of the z=1.53 quasar 3C270.1 with the Spitzer Space Telescope at 3.6-24 micron and with the 6.5-m MMT in the z'- and Y-bands allow detection of potential cluster members via photometric redshifts. Compared with nearby control fields, there is an excess of 11 extremely red objects (EROs) at 1.33 < z_phot < 1.73, consistent with a proto-cluster around the quasar. The spectral energy distributions (SEDs) of 3/4 of the EROs are better fitted with passive elliptical galaxies than withdust-reddened starbursts, and of four sources well-detected on an archival HST snapshot image, all have undisturbed morphologies. However, one ERO, not covered by the HST image, is a double source with 0.8" separation on the z' image and a marginal (2sigma) 24 micron detection indicating a dust-enshrouded starburst. The EROs are more luminous than L* (H = -23.6 AB mag at z=1.5).

12 pages, 7 figures, accepted by ApJ

References in corpus (15)

• Clusters of Galaxies in the First Half of the Universe from the IRAC Shallow Survey
• The Massive Hosts of Radio Galaxies Across Cosmic Time
• Photometric redshifts in the SWIRE Survey
• The XMM Cluster Survey: A Massive Galaxy Cluster at z=1.45
• The Nascent Red Sequence at z~2
• The Evolution of Dusty Star Formation and Stellar Mass Assembly in Clusters: Results from the IRAC 3.6um, 4.5um, 5.8um and 8.0um Cluster Luminosity Functions
• XMM-LSS discovery of a z=1.22 galaxy cluster
• The rest-frame $K$-band luminosity function of galaxies in clusters to $z=1.3$
• Near- and mid-infrared photometry of high-redshift 3CR sources
• Galaxy clusters at 0.6 < z < 1.4 in the UKIDSS Ultra Deep Survey Early Data Release
• Large-scale structure of Lyman break galaxies around a radio galaxy protocluster at z~4
• Spitzer Observations of the Prototypical Extremely Red Objects HR10 and LBDS53W091: Separating Dusty Starbursts from Old Elliptical Galaxies
• AEGIS: Chandra Observation of DEEP2 Galaxy Groups and Clusters
• Distant galaxy clusters in the COSMOS field found by HIROCS
• Discovery of an overdensity of faint red galaxies in the vicinity of the z=1.786 radio galaxy 3C 294

Cited by in corpus (6)

• The Mid-Infrared Environments of High-Redshift Radio Galaxies
• Three candidate clusters of galaxies at redshift ~1.8: the "missing link" between protoclusters and local clusters?
• Chandra X-ray Observations of the redshift 1.53, radio-loud quasar: 3C 270.1
• Galaxy overdensities around 3C radio galaxies and quasars at $1<z<2.5$ revealed by Spitzer $3.6/4.5\mu$m and Pan-STARRS
• Clustering of red and blue galaxies around high-redshift 3C radio sources as seen by the Hubble Space Telescope
• Three candidate clusters around high redshift radio-loud sources: MG1 J04426+0202, 3C 068.2, MS 1426.9+1052