A 100 pc-scale fast and dense outflow in the narrow-line Seyfert 1 galaxy IRAS 04576+0912

Abstract

We report the initial results of an adaptive-optics-assisted, optical integral-field-unit observation of IRAS 04576+0912, the nearest (z = 0.039) active galactic nucleus with a prominent blueshift/tail in [O III] emission from a sample of such objects that we have collected from the literature. We aim at addressing the putative quasar-mode feedback process with Subaru/Kyoto 3D II+AO188. The optical waveband (6400-7500 Å) enables us to measure the gas density via the [S II] doublets, in contrast to earlier near-IR studies. Since the fast [O III] outflow happens only around rapidly growing central black holes, this object is suitable for investigating the black hole-galaxy coevolution. The obtained data cube exhibits a blue tail in the [S II] emission at many lenslets. By fitting the spectrum with the high excess flux at the [S II] bluetail, we find a fast (∼860 km s−1), dense (>3000 cm−3), wide-angle, and offset outflow in central 100 pc scales. Although the large opening angle and the high gas outflow-to-accretion ratio may favor the feedback hypothesis, the inferred kinetic power injection rate of this ionized gas outflow seems insufficient to influence the whole host galaxy. A conventional assumption of a low density must have overestimated the feedback process.