2013MNRAS.436.2576L

The prevalence and energetics of quasar feedback is a major unresolved problem in galaxy formation theory. In this paper, we present Gemini Integral Field Unit observations of ionized gas around 11 luminous, obscured, radio-quiet quasars at z ∼ 0.5 out to ∼ 15kpc from the quasar; specifically, we measure the kinematics and morphology of [OIII] λ5007 Å emission. The round morphologies of the nebulae and the large line-of-sight velocity widths (with velocities containing 80 percent of the emission as high as 10³km/s) combined with relatively small velocity difference across them (from 90 to 520km/s) point towards wide-angle quasi-spherical outflows. We use the observed velocity widths to estimate a median outflow velocity of 760km/s, similar to or above the escape velocities from the host galaxies. The line-of-sight velocity dispersion declines slightly towards outer parts of the nebulae (by 3 percent/kpc on average). The majority of nebulae show blueshifted excesses in their line profiles across most of their extents, signifying gas outflows. For the median outflow velocity, we find {dot}E_kin between 4x10⁴⁴ and 3x10⁴⁵ erg/s and {dot}M between 2x10³ and 2x10⁴M_☉/yr. These values are large enough for the observed quasar winds to have a significant impact on their host galaxies. The median rate of converting bolometric luminosity to kinetic energy of ionized gas clouds is ∼ 2 percent. We report four new candidates for `superbubbles' - outflows that may have broken out of the denser regions of the host galaxy.