Binary quasars at high redshift. II. Sub-Mpc clustering at z ∼ 3-4

Yue Shen, Joseph F. Hennawi, Francesco Shankar, Adam D. Myers, Michael A. Strauss, S. G. Djorgovski, Xiaohui Fan, Carlo Giocoli, Ashish Mahabal, Donald P. Schneider, David H. Weinberg

Research output: Contribution to journalArticle

45 Scopus citations


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.

Original languageEnglish (US)
Pages (from-to)1693-1698
Number of pages6
JournalAstrophysical Journal
Issue number2
Publication statusPublished - Aug 20 2010



  • Black hole physics
  • Cosmology: observations
  • Galaxies: active
  • Large-scale structure of universe
  • Quasars: general
  • Surveys

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Shen, Y., Hennawi, J. F., Shankar, F., Myers, A. D., Strauss, M. A., Djorgovski, S. G., ... Weinberg, D. H. (2010). Binary quasars at high redshift. II. Sub-Mpc clustering at z ∼ 3-4. Astrophysical Journal, 719(2), 1693-1698.