Clustering of Dust-Obscured Galaxies at z ~ 2

Abstract

We present the angular autocorrelation function of 2603 dust-obscured galaxies (DOGs) in the Boötes field of the NOAO Deep Wide-Field Survey. DOGs are red, obscured galaxies, defined as having -->R − [ 24] ≥ 14 ( -->F24/FR 1000). Spectroscopy indicates that they are located at -->1.5 z 2.5. We find strong clustering, with -->r0 = 7.40−0.84+1.27 -->h−1 Mpc for the full -->F24 > 0.3 mJy sample. The clustering and space density of the DOGs are consistent with those of submillimeter galaxies, suggestive of a connection between these populations. We find evidence for luminosity-dependent clustering, with the correlation length increasing to -->r0 = 12.97−2.64+4.26 -->h−1 Mpc for brighter ( -->F24 > 0.6 mJy) DOGs. Bright DOGs also reside in richer environments than fainter ones, suggesting these subsamples may not be drawn from the same parent population. The clustering amplitudes imply average halo masses of -->log M = 12.2−0.2+0.3 M☉ for the full DOG sample, rising to -->log M = 13.0−0.3+0.4 M☉ for brighter DOGs. In a biased structure formation scenario, the full DOG sample will, on average, evolve into ~ -->3L* present-day galaxies, whereas the most luminous DOGs may evolve into brightest cluster galaxies.