* Astronomy

Title: Gas inflows towards the nucleus of the Seyfert 2 galaxy NGC1667
Author: llan Schnorr-Müller, Thaisa Storchi-Bergmann, Fabricio Ferrari, Neil M. Nagar

We use optical spectra from the inner 2 x 3kpc^2 of the Seyfert 2 galaxy NGC1667, obtained with the GMOS integral field spectrograph on the Gemini South telescope at a spatial resolution of \approx 240pc, to assess the feeding and feedback processes in this nearby AGN. We have identified two gaseous kinematical components in the emission line profiles: a broader component (sigma \approx 400km s^-1) which is observed in the inner 1-2arcsec and a narrower component (sigma \approx 200km s^-1) which is present over the entire field-of-view. We identify the broader component as due to an unresolved nuclear outflow. The narrower component velocity field shows strong isovelocity twists relative to a rotation pattern, implying the presence of strong non-circular motions. The subtraction of a rotational model reveals that these twists are caused by outflowing gas in the inner \approx 1arcsec, and by inflows associated with two spiral arms at larger radii. We calculate an ionized gas mass outflow rate of \dot{M}_{out} \approx 0.16 solar masses yr^-1. We calculate the net gas mass flow rate across a series of concentric rings, obtaining a maximum mass inflow rate in ionized gas of \approx 2.8 solar masses year^-1 at 800pc from the nucleus, which is two orders of magnitude larger than the accretion rate necessary to power this AGN. However, as the mass inflow rate decreases at smaller radii, most of the gas probably will not reach the AGN, but accumulate in the inner few hundred parsecs. This will create a reservoir of gas that can trigger the formation of new stars.

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