Feeding versus feedback in AGN from near-infrared IFU observations XI: NGC 2110

Abstract

We present a two-dimensional mapping of the gas flux distributions, as well as of the gas and stellar kinematics in the inner 220 pc of the Seyfert galaxy NGC 2110, using K-band integral field spectroscopy obtained with the Gemini NIFS at a spatial resolution of ≈ 24 pc and spectral resolution of ≈ 40 km s −1 . The H 2 λ 2.1218 µm emission extends over the whole field-of-view and is attributed to heating by X-rays from the AGN and/or by shocks, while the Brγ emission is restricted to a bi-polar region extending along the South-East-NorthWest direction. The masses of the warm molecular gas and of the ionized gas are M H 2 ≈ 1.4 × 10 3 M ⊙ and M H II ≈ 1.8 × 10 6 M ⊙ , respectively. The stellar kinematics present velocity dispersions reaching 250 km s −1 , and a rotation pattern reaching an amplitude of 200 km s −1 . The gas velocity fields present a similar rotation pattern but also additional components that we attribute to inflows and outflows most clearly observed in the molecular gas emission. The inflows are observed beyond the inner 70 pc and are associated to a spiral arm seen in blueshift to the North-East and another in redshift to the South-West. We have estimated a mass inflow rate in warm molecular gas of ≈ 4.6 × 10 −4 M ⊙ yr −1 . Within the inner 70 pc, another kinematic component is observed in the H 2 emission that can be interpreted as due to a bipolar nuclear outflow oriented along the East-West direction, with a mass-outflow rate of ≈ 4.3 × 10 −4 M ⊙ yr −1 in warm H 2 .

Gemini NIFS survey of feeding and feedback in nearby active galaxies – III. Ionized versus warm molecular gas masses and distributions

“…Our ultimate goal is to investigate possible correlations between measured properties (as gas masses and densities, mass inflow and outflow rates and kinetic power of the outflows) and the AGN luminosity. Results for individual galaxies of the sample have been already presented in previous papers by our group: NGC 4051 (Riffel et al 2008a, NGC 4151 (Storchi-Bergmann et al 2009, 2010Riffel et al 2009a), Mrk 1066 (Riffel et al 2010b;Ramos Almeida et al 2009;Riffel et al 2017), Mrk 1157 Riffel et al , 2017, NGC 1068 (Storchi-Bergmann et al 2012;Riffel et al 2014a; Barbosa et al 2014), Mrk 79 (Riffel et al 2013), Mrk 766 (Schönell et al 2014;Riffel et al 2017), NGC5929 (Riffel et al 2014b, NGC 2110 (Diniz et al 2015), NGC 5548 Riffel et al 2017), NGC 788, NGC 3227, NGC 3516, NGC 4235, NGC 4388, NGC 5506, NGC 1052 and Mrk 607 .…”

“…Riffel et al 2018) and others show that the molecular and ionized gas have distinct spacial distributions and kinematics at these scales: the former is usually more restricted to the plane of galaxies, with the kinematics being dominated by rotation in the disk in most cases, and presenting also signatures of inflows in some cases; the latter traces a more disturbed medium, usually associated to outflows from the AGN, but frequently showing also a disk rotation component (e.g. Riffel et al 2010aRiffel et al , 2013Mazzalay et al 2014; Barbosa et al 2014;Diniz et al 2015). Our previous studies led to the conclusion that, while the ionized gas emission can be considered a tracer of the AGN feedback, the molecular gas emission is usually a tracer of its feeding.…”

Observational constraints on the feeding of supermassive black holes

“…One method used to look for inflows is the fit of the stellar velocity field by a rotation model, then use this model to fit the gaseous velocity field allowing for variation in the rotation amplitude that is usually higher for the gas (due to its lower velocity dispersion as it is usually more confined to the galaxy plane than the stars), and then subtract this model from the gasesous velocity field [192]. The cases of inflows are revealed when the residuals show mostly blueshifts in the far side of the galaxy and redshifts in the near side.…”

Gemini NIFS survey of feeding and feedback processes in nearby active galaxies – I. Stellar kinematics

“…Usually these studies are based on high-spatial resolution integral field spectroscopy (IFS; e.g. Fathi et al 2006;Storchi-Bergmann et al 2007Barbosa et al 2009Barbosa et al , 2014Hicks et al 2009Hicks et al , 2013Sánchez et al 2009;Riffel & Storchi-Bergmann 2011a;Riffel et al 2013;Mazzalay et al 2014;Riffel et al 2014;Schönell et al 2014;Diniz et al 2015;Fischer et al 2017). To isolate and quantify gas streaming motions towards the centre of galaxies or gas outflows from the nucleus through the gas kinematics, it is necessary to properly map the motions of the gas due to the gravitational potential of the galaxy.…”