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A 100-pc Scale, Fast and Dense Outflow in Narrow-Line Seyfert 1 Galaxy IRAS04576+0912

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 Publication date 2018
  fields Physics
and research's language is English




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We report the initial result of an adaptive-optics assisted, optical integral-field-unit observation on IRAS04576+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 AA) 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 blue tail in the [S II] emission at many lenslets. By fitting the spectrum with the high excess flux at the [S II] blue tail, we find the fast (~ 860 km/s), dense (>3000/cc), wide-angle and offset outflow in central 100-pc scales. Although the large opening angle and the high gas outflow-to-accretion ratio may favour 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.



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