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Register a new userFeeding Versus Feedback in AGN from Near-Infrared IFU Observations XI: NGC 2110
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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 ~24pc and spectral resolution of ~40 km/s. The H2 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 Brgamma emission is restricted to a bi-polar region extending along the South-East-North-West direction. The masses of the warm molecular gas and of the ionized gas are ~1.4x10^3 Msun and ~1.8x10^6 Msun, respectively. The stellar kinematics present velocity dispersions reaching 250km/s and a rotation pattern reaching an amplitude of 200 km/s. 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 ~4.6x10^-4 Msun/year. Within the inner 70 pc, another kinematic component is observed in the H2 emission that can be interpreted as due to a bipolar nuclear outflow oriented along the East-West direction, with a mass-outflow rate of ~4.3x10^-4 Msun/year in warm H2.
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We report ALMA observations of CO(3-2) emission in the Seyfert 2 double-barred galaxy NGC1433, at the unprecedented spatial resolution of 0.5=24 pc. Our aim is to probe AGN feeding and feedback phenomena through the morphology and dynamics of the gas inside the central kpc. The CO map, which covers the whole nuclear region (nuclear bar and ring), reveals a nuclear gaseous spiral structure, inside the nuclear ring encircling the nuclear stellar bar. This gaseous spiral is well correlated with the dusty spiral seen in Hubble Space Telescope images. The nuclear spiral winds up in a pseudo-ring at 200 pc radius, which might correspond to the inner ILR. Continuum emission is detected at 0.87 mm only at the very centre, and its origin is more likely thermal dust emission than non-thermal emission from the AGN. It might correspond to the molecular torus expected to exist in this Seyfert 2 galaxy. The HCN(4-3) and HCO+(4-3) lines were observed simultaneously, but only upper limits are derived, with a ratio to the CO(3-2) line lower than 1/60 at 3sigma, indicating a relatively low abundance of very dense gas. The kinematics of the gas over the nuclear disk reveal rather regular rotation only slightly perturbed by streaming motions due to the spiral; the primary and secondary bars are too closely aligned with the galaxy major or minor axis to leave a signature in the projected velocities. Near the nucleus, there is an intense high-velocity CO emission feature redshifted to 200 km/s (if located in the plane), with a blue-shifted counterpart, at 2 (100 pc) from the centre. While the CO spectra are quite narrow in the centre, this wide component is interpreted as an outflow involving a molecular mass of 3.6 10^6 Mo and a flow rate 7 Mo/yr. The flow could be in part driven by the central star formation, but is mainly boosted by the AGN through its wind or radio jets.
We have used the Gemini Near-infrared Integral Field Spectrograph (NIFS) to map the emission-line intensity distributions and ratios in the Narrow-Line Region (NLR) of the Seyfert galaxy NGC 4151 in the Z, J, H and K bands at a resolving power ~ 5000, covering the inner 200 pc x 300 pc of the galaxy at a spatial resolution of 8 pc. We present intensity distributions I(r) in 14 emission lines. (1) For the ionized gas, I(r) is extended to ~ 100 pc from the nucleus along pos. angle PA=60/240 deg-- NE--SW), consistent with an origin in the known biconical outflow; while for the recombination lines I(r) ~ r^-1, for the forbidden lines I(r) is flat (r^0). (2) The H_2 emission lines intensity distributions avoid the region of the bicone, extending to r ~ 60 pc, perpendicular to the bicone axis, supporting an origin for the H_2-emitting gas in the galaxy plane. (3) The coronal lines show a steep intensity profile, described by r^-2. Using the line-ratio maps [Fe II]1.644/1.257 and Pa_b/Br_g we obtain a reddening of E(B-V)~0.5 along the NLR and E(B-V)>1 at the nucleus. Our line-ratio map [Fe II] 1.257/[P II] 1.189 is the first such map of an extragalactic source. Together with the [Fe II]/Pa_b map, these line ratios correlate with the radio intensity distribution, mapping the effects of shocks produced by the radio jet, which probably release the Fe locked in grains and produce the enhancement of the [Fe II] emission observed at ~ 1 arcsec from the nucleus. At these regions, we obtain densities N_e ~4000 cm^-3 and temperatures T_e ~ 15000K for the [Fe II]-emitting gas. For the H_2-emitting gas we obtain T ~ 2100K. The distinct intensity distributions, physical properties and locations of the ionized and molecular gas suggest that the H_2-emitting gas traces the AGN feeding, while the ionized gas traces its feedback.
Feedback by Active Galactic Nuclei is often divided into quasar and radio mode, powered by radiation or radio jets, respectively. Both are fundamental in galaxy evolution, especially in late-type galaxies, as shown by cosmological simulations and observations of jet-ISM interactions in these systems. We compare AGN feedback by radiation and by collimated jets through a suite of simulations, in which a central AGN interacts with a clumpy, fractal galactic disc. We test AGN of $10^{43}$ and $10^{46}$ erg/s, considering jets perpendicular or parallel to the disc. Mechanical jets drive the more powerful outflows, exhibiting stronger mass and momentum coupling with the dense gas, while radiation heats and rarifies the gas more. Radiation and perpendicular jets evolve to be quite similar in outflow properties and effect on the cold ISM, while inclined jets interact more efficiently with all the disc gas, removing the densest $20%$ in $20$ Myr, and thereby reducing the amount of cold gas available for star formation. All simulations show small-scale inflows of $0.01-0.1$ M$_odot$/yr, which can easily reach down to the Bondi radius of the central supermassive black hole (especially for radiation and perpendicular jets), implying that AGN modulate their own duty cycle in a feedback/feeding cycle.
We explore the kinematics of the stars, ionized gas, and warm molecular gas in the Seyfert 2 galaxy Mrk~3 (UGC~3426) on nuclear and galactic scales with {it Gemini} Near-Infrared Field Spectrograph (NIFS) observations, previous {it Hubble Space Telescope} data, and new long-slit spectra from the {it Apache Point Observatory} ({it APO}) 3.5 m telescope. The {it APO} spectra are consistent with our previous suggestion that a galactic-scale gas/dust disk at PA $=$ 129arcdeg, offset from the major axis of the host S0 galaxy at PA $=$ 28arcdeg, is responsible for the orientation of the extended narrow-line region (ENLR). The disk is fed by an H~I tidal stream from a gas-rich spiral galaxy (UGC~3422) $sim$100 kpc to the NW of Mrk 3, and is ionized by the AGN to a distance of at least $sim$20arcsec ($sim$5.4 kpc) from the central supermassive black hole (SMBH). The kinematics within at least 320 pc of the SMBH are dominated by outflows with radial (line of sight) velocities up to 1500 km s$^{-1}$ in the ionized gas and 500 km s$^{-1}$ in the warm molecular gas, consistent with in situ heating, ionization, and acceleration of ambient gas to produce the narrow-line region (NLR) outflows. There is a disk of ionized and warm molecular gas within $sim$400 pc of the SMBH that has re-oriented close to the stellar major axis but is counter-rotating, consistent with claims of external fueling of AGN in S0 galaxies.
Supermassive black hole (SMBH) feeding and feedback processes are often considered as disjoint and studied independently at different scales, both in observations and simulations. We encourage to adopt and unify three physically-motivated scales for feeding and feedback (micro - meso - macro ~ mpc - kpc - Mpc), linking them in a tight multiphase self-regulated loop. We pinpoint the key open questions related to this global SMBH unification problem, while advocating for the extension of novel mechanisms best observed in massive halos (such as chaotic cold accretion) down to low-mass systems. To solve such challenges, we provide a set of recommendations that promote a multiscale, multiwavelength, and interdisciplinary community.
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