Feeding versus feedback in AGN from near-infrared IFU observations: the case of Mrk 766

Abstract

We have mapped the emission-line flux distributions and ratios as well as the gaseous kinematics of the inner 450 pc radius of the type 1 Seyfert galaxy Mrk 766 using integral field near-infrared J-and K l -band spectra obtained with the Gemini Near Infrared Integral Field Spectrograph at a spatial resolution of 60 pc and velocity resolution of 40 km s −1 . Emission-line flux distributions in ionized and molecular gas extend up to ≈ 300 pc from the nucleus. Coronal [S IX] λ1.2523 µm line emission is resolved, being extended up to 150 pc from the nucleus. At the highest flux levels, the [Fe II] λ1.257 µm line emission is most extended to the south-east, where a radio jet has been observed. The emission-line ratios [Fe II] λ1.2570 µm/Paβ and H 2 λ2.1218 µm/Brγ show a mixture of Starburst and Seyfert excitation; the Seyfert excitation dominates at the nucleus, to the north-west and in an arc-shaped region between 0.2 and 0.6 arcsec to the south-east at the location of the radio jet. A contribution from shocks at this location is supported by enhanced [Fe II]/[P II] line ratios and increased [Fe II] velocity dispersion. The gas velocity field is dominated by rotation that is more compact for H 2 than for Paβ, indicating that the molecular gas has a colder kinematics and is located in the galaxy plane. There is about 10 3 M of hot H 2 , implying ≈10 9 M of cold molecular gas. At the location of the radio jet, we observe an increase in the [Fe II] velocity dispersion (150 km s −1 ), as well as both blueshift and redshifts in the channel maps, supporting the presence of an outflow there. The ionized gas mass outflow rate is estimated to be ≈10 M yr −1 , and the power of the outflow ≈0.08 L bol .

Quantifying AGN-driven metal-enhanced outflows in chemodynamical simulations

“…We can also estimate the mass outflow rate to be ∼400 M yr −1 , which lies within the observed range 10 M yr −1 Ṁ out 10 3 M yr −1 (e.g. Feruglio et al 2010;Schönell et al 2014). The outflowing gas soon slows and entrains more gas, eventually stalling ∼100 kpc from the BH by t = 9.245 Gyr, when the rerun simulation ends.…”

A low-luminosity type-1 QSO sample

“…The AGNIFS group obtained masses in a range of 66 M ≤ M H 2 ≤ 3300 M and 0.1 × 10 6 M ≤ M H  ≤ 17 × 10 6 M in the nuclear regions of nearby galaxies (Riffel et al 2008(Riffel et al , 2010Storchi-Bergmann et al 2009;Schönell et al 2014). We conclude that the LLQSO HE 1029-1831 has a large reservoir of cold molecular gas that is needed and apparently used for both star formation and black hole fueling.…”

“…8 right). Previous studies (e.g., Riffel et al 2010;Schönell et al 2014) show that the centers of active galaxies often show line ratios characteristic of a mixture of starburst and AGN excitation.…”

Near-Infrared Spectroscopy of Nearby Seyfert Galaxies: Is There Evidence for Shock Excitation in Narrow-Line Regions?

“…Though the [Fe ii]/[P ii] flux ratio is an interesting tool to explore the nature of the AGN feedback at the NLR scale, this emission-line flux ratio has not been measured in many objects so far (∼ 20 objects; e.g., Oliva et al 2001;Ramos Almeida et al 2006Riffel et al 2006Riffel et al , 2013Jackson & Beswick 2007;Krajnović et al 2007;Hashimoto et al 2011;Riffel & Storchi-Bergmann 2011;Schönell et al 2014;Riffel et al 2015). Therefore it is hard to carry out various statistical analyses on the [Fe ii]/[P ii] flux ratio currently.…”