Binary Quasars at High Redshift. II. Sub-Mpc Clustering at z ~ 3-4

The Astrophysical Journal (Impact Factor: 5.99). 08/2010; 719(2):1693. DOI: 10.1088/0004-637X/719/2/1693
Source: arXiv


We present measurements of the small-scale (0.1 r 1 h –1 Mpc) quasar two-point correlation function at z>2.9, for a flux-limited (i < 21) sample of 15 binary quasars compiled by Hennawi et al. The amplitude of the small-scale clustering increases from z ~ 3 to z ~ 4. The small-scale clustering amplitude is comparable to or lower than power-law extrapolations (assuming a fixed slope γ = 2) from the large-scale correlation function of the i < 20.2 quasar sample from the Sloan Digital Sky Survey. Using simple prescriptions relating quasars to dark matter halos, we model the observed small-scale clustering with halo occupation models. We found that the level of small-scale clustering favors an active fraction of black holes in (M 1013 h –1 M ☉) satellite halos fs 0.1 at z 3.

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