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Register a new userAn outflow in the Seyfert ESO 362-G18 revealed by Gemini-GMOS/IFU Observations
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We present two-dimensional stellar and gaseous kinematics of the inner 0.7 $times$ 1.2 kpc$^{2}$ of the Seyfert galaxy ESO 362-G18, derived from optical spectra obtained with the GMOS/IFU on the Gemini South telescope at a spatial resolution of $approx$170 pc and spectral resolution of 36 km s$^{-1}$. ESO 362-G18 is a strongly perturbed galaxy of morphological type Sa or S0/a, with a minor merger approaching along the NE direction. Previous studies have shown that the [OIII] emission shows a fan-shaped extension of $approx$ 10arcsec to the SE. We detect the [OIII] doublet, [NII] and H${alpha}$ emission lines throughout our field of view. The stellar kinematics is dominated by circular motions in the galaxy plane, with a kinematic position angle of $approx$137$^{circ}$. The gas kinematics is also dominated by rotation, with kinematic position angles ranging from 122$^{circ}$ to 139$^{circ}$. A double-Gaussian fit to the [OIII]$lambda$5007 and H${alpha}$ lines, which have the highest signal to noise ratios of the emission lines, reveal two kinematic components: (1) a component at lower radial velocities which we interpret as gas rotating in the galactic disk; and (2) a component with line of sight velocities 100-250 km s$^{-1}$ higher than the systemic velocity, interpreted as originating in the outflowing gas within the AGN ionization cone. We estimate a mass outflow rate of 7.4 $times$ 10$^{-2}$ M$_{odot}$ yr$^{-1}$ in the SE ionization cone (this rate doubles if we assume a biconical configuration), and a mass accretion rate on the supermassive black hole (SMBH) of 2.2 $times$ 10$^{-2}$ M$_{odot}$ yr$^{-1}$. The total ionized gas mass within $sim$84 pc of the nucleus is 3.3 $times$ 10$^{5}$ M$_{odot}$; infall velocities of $sim$34 km s$^{-1}$ in this gas would be required to feed both the outflow and SMBH accretion.
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