Galactic-scale emission-line outflow from the radio-loud quasar 3C 191

TL;DR

This study uses integral-field spectroscopy to map and analyze a galactic outflow from quasar 3C 191 at z~2, revealing a biconical structure with measured energetics, and comparing emission and absorption line data.

Contribution

It provides the first detailed IFS mapping of the outflow in emission lines for quasar 3C 191, complementing absorption line studies and estimating outflow properties.

Findings

Outflow has a biconical structure extending up to 11 kpc.

Mass outflow rate estimated at 9.5-13.4 solar masses per year.

Kinetic luminosity is a small fraction of bolometric luminosity, indicating weak feedback.

Abstract

Quasar feedback is routinely invoked as an indispensable ingredient in galaxy formation models. Galactic outflows are a crucial agent of quasar feedback that frequently manifest themselves in absorption and emission lines. Measuring the size and energetics of outflows based on absorption lines remains a challenge, and integral-field spectroscopy (IFS) mapping in emission lines is complementary. We present a VLT/SINFONI IFS mapping of quasar 3C 191 at $z \sim 2$, in which the outflow has been analyzed in absorption line spectroscopy. Three components are found based on the morphology and kinetics of [OIII]-emitting gas: a unshifted component which consistent with the systemic redshift and the location of the nucleus, a blueshifted in the north, and a redshifted in the south. The latter two components have velocities $\sim$ 600 km s$^{-1}$ and projected extents of 5 and 11 kpc, respectively, suggesting a biconical outflow structure. The blueshifted component's velocity is consistent with that derived from absorption lines. Using the electron density measured by the absorption lines and the luminosity and velocity of [OIII] outflow, we derive the mass outflow rate to be $\dot{M} \sim $ 9.5-13.4 M$_\odot$ yr$^{-1}$ and kinetic luminosity $\dot{E}_{\rm kin}$ ~ 2.5-3.7 $\times 10^{42}$ erg s$^{-1}$, consistent with absorption line analyses with VLT/Xshooter spectrum. The kinetic luminosity is only 0.01% of the bolometric luminosity, rendering a relatively weak outflow compared to typical expectation for effective feedback.