The co-evolution of black hole growth and star formation from a
  cross-correlation analysis between quasars and the cosmic infrared background
  We present the first cross-correlation measurement between Sloan Digital Sky
Survey (SDSS) Type 1 quasars and the cosmic infrared background (CIB) measured
by Herschel. The distribution of the quasars at 0.15<z<3.5 covers the redshift
range where we expect most of the CIB to originate. We detect the sub-mm
emission of the quasars, which dominates on small scales, as well as correlated
emission from dusty star-forming galaxies (DSFGs) dominant on larger scales.
The mean sub-mm flux densities of the DR7 quasars (median redshift <z>=1.4) is
$11.1^{+1.6}_{-1.4}$, $7.1^{+1.6}_{-1.3}$ and $3.6^{+1.4}_{-1.0}$ mJy at 250,
350 and 500 microns, respectively, while the mean sub-mm flux densities of the
DR9 quasars (<z>=2.5) is $5.7^{+0.7}_{-0.6}$, $5.0^{+0.8}_{-0.7}$ and
$1.8^{+0.5}_{-0.4}$ mJy. We find that the correlated sub-mm emission includes
both the emission from satellite DSFGs in the same halo as the central quasar
and the emission from DSFGs in separate halos (correlated with the
quasar-hosting halo). The amplitude of the one-halo term is ~10 times smaller
than the sub-mm emission of the quasars, implying the the satellites have a
lower star-formation rate than the quasars. The satellite fraction for the DR7
quasars is $0.008^{+0.008}_{-0.005}$ and the host halo mass scale for the
central and satellite quasars is $10^{12.36\pm0.87}$ M$_{\odot}$ and
$10^{13.60\pm0.38}$ M$_{\odot}$, respectively. The satellite fraction of the
DR9 quasars is $0.065^{+0.021}_{-0.031}$ and the host halo mass scale for the
central and satellite quasars is $10^{12.29\pm0.62}$ M$_{\odot}$ and
$10^{12.82\pm0.39}$ M$_{\odot}$, respectively. Thus, the typical halo
environment of the SDSS Type 1 quasars is found to be similar to that of DSFGs,
which supports the generally accepted view that dusty starburst and quasar
activity are evolutionarily linked.
