Low-redshift QSOs in SDSS Stripe 82

We have compared the <1Mpc scale environments of 302 quasars that were resolved in our recent study to those of 288 inactive galaxies with closely matched redshifts. Crucially, the luminosities of the inactive galaxies and the quasar host galaxies are also closely matched, unlike in most previous studies.

The environmental overdensities were studied by measuring the number density of galaxies within a projected distance of 200kpc to 1Mpc. The galaxy number density of the quasar environments is comparable to that of the inactive galaxies with similar luminosities, both classes of objects showing significant excess compared to the background galaxy density for distances <400kpc. There is no significant dependence of the galaxy number density on redshift, quasar or host galaxy luminosity, black hole mass or radio loudness.