Integral Field Spectroscopy of AGN Absorption Outflows: Mrk 509 and IRAS F04250-5718

TL;DR

This study uses integral field spectroscopy to directly measure the size, velocity, and energetics of AGN outflows, confirming previous UV absorption line estimates and demonstrating the effectiveness of this method.

Contribution

First direct spatial measurements of AGN outflow properties that validate UV absorption line analyses for determining outflow energetics.

Findings

Outflows in Mrk 509 and IRAS F04250-5718 have radii of 1.2 and 2.9 kpc.

Measured outflow velocities are approximately 290 and 580 km/s.

Mass flow rates are around 5 and >1 solar masses per year.

Abstract

Ultravoilet (UV) absorption lines provide abundant spectroscopic information enabling the probe of the physical conditions in AGN outflows, but the outflow radii (and the energetics consequently) can only be determined indirectly. In this paper, we present the first direct test of these determinations using integral field unit (IFU) spectroscopy. We have conducted Gemini IFU mapping of the ionized gas nebulae surrounding two AGNs, whose outflow radii have been constrained by UV absorption line analyses. In Mrk 509, we find a quasi-spherical outflow with a radius of 1.2 kpc and a velocity of $\sim290$ km s$^{-1}$, while IRAS F04250$-$5718 is driving a biconical outflow extending out to 2.9 kpc, with a velocity of $\sim580$ km s$^{-1}$ and an opening angle of $\sim70^{\circ}$. The derived mass flow rate is $\sim5$ and $>1$ M$_{\odot}$ yr$^{-1}$, respectively, and the kinetic luminosity is $\gtrsim1\times10^{41}$ erg s$^{-1}$ for both. Adopting the outflow radii and geometric parameters measured from IFU, absorption line analyses would yield mass flow rates and kinetic luminosities in agreement with the above results within a factor of $\sim2$. We conclude that the spatial locations, kinematics and energetics revealed by this IFU emission-line study are consistent with pre-existing UV absorption line analyses, providing a long-awaited direct confirmation of the latter as an effective approach for characterizing outflow properties.