On the Clustering of Compact Galaxy Pairs in Dark Matter Haloes
  We analyze the clustering of photometrically selected galaxy pairs by using
the halo-occupation distribution (HOD) model. We measure the angular two-point
auto-correlation function, $\omega(\theta)$, for galaxies and galaxy pairs in
three volume-limited samples and develop an HOD to model their clustering. Our
results are successfully fit by these HOD models, and we see the separation of
"1-halo" and "2-halo" clustering terms for both single galaxies and galaxy
pairs. Our clustering measurements and HOD model fits for the single galaxy
samples are consistent with previous results. We find that the galaxy pairs
generally have larger clustering amplitudes than single galaxies, and the
quantities computed during the HOD fitting, e.g., effective halo mass,
$M_{eff}$, and linear bias, $b_{g}$, are also larger for galaxy pairs. We find
that the central fractions for galaxy pairs are significantly higher than
single galaxies, which confirms that galaxy pairs are formed at the center of
more massive dark matter haloes. We also model the clustering dependence of the
galaxy pair correlation function on redshift, galaxy type, and luminosity. We
find early-early pairs (bright galaxy pairs) cluster more strongly than
late-late pairs (dim galaxy pairs), and that the clustering does not depend on
the luminosity contrast between the two galaxies in the compact group.
