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We report on the determination of electron densities, and their impact on the outflow masses and rates, measured in the central few hundred parsecs of 11 local luminous active galaxies. We show that the peak of the integrated line emission in the active galactic nuclei (AGN) is significantly offset from the systemic velocity as traced by the stellar absorption features, indicating that the profiles are dominated by outflow. In contrast, matched inactive galaxies are characterized by a systemic peak and weaker outflow wing. We present three independent estimates of the electron density in these AGN, discussing the merits of the different methods. The electron density derived from the [S  ii ] doublet is significantly lower than that found with a method developed in the last decade using auroral and transauroral lines, as well as a recently introduced method based on the ionization parameter. The reason is that, for gas photoionized by an AGN, much of the [S  ii ] emission arises in an extended partially ionized zone where the implicit assumption that the electron density traces the hydrogen density is invalid. We propose ways to deal with this situation and we derive the associated outflow rates for ionized gas, which are in the range 0.001–0.5 M⊙ yr−1 for our AGN sample. We compare these outflow rates to the relation between |$\dot{M}_{\rm out}$| and L AGN in the literature, and argue that it may need to be modified and rescaled towards lower mass outflow rates. [ABSTRACT FROM AUTHOR]

We report on our combined analysis of HST , VLT/MUSE, VLT/SINFONI, and ALMA observations of the local Seyfert 2 galaxy, NGC 5728 to investigate in detail the feeding and feedback of the active galactic nucleus (AGN). The data sets simultaneously probe the morphology, excitation, and kinematics of the stars, ionized gas, and molecular gas over a large range of spatial scales (10 pc to 10 kpc). NGC 5728 contains a large stellar bar that is driving gas along prominent dust lanes to the inner 1 kpc where the gas settles into a circumnuclear ring. The ring is strongly star forming and contains a substantial population of young stars as indicated by the lowered stellar velocity dispersion and gas excitation consistent with H  ii regions. We model the kinematics of the ring using the velocity field of the CO (2–1) emission and stars and find it is consistent with a rotating disc. The outer regions of the disc, where the dust lanes meet the ring, show signatures of inflow at a rate of 1 M |$\odot$|  yr−1. Inside the ring, we observe three molecular gas components corresponding to the circular rotation of the outer ring, a warped disc, and the nuclear stellar bar. The AGN is driving an ionized gas outflow that reaches a radius of 250 pc with a mass outflow rate of 0.08 M |$\odot$|  yr−1 consistent with its luminosity and scaling relations from previous studies. While we observe distinct holes in CO emission which could be signs of molecular gas removal, we find that largely the AGN is not disrupting the structure of the circumnuclear region. [ABSTRACT FROM AUTHOR]

We present two-dimensional ionized gas and stellar kinematics in the inner 1.4 × 1.9 kpc2 of the Seyfert 2 galaxy ESO 153-G20 obtained with the Gemini-South/Gemini multi-object spectrograph integral field unit (GMOS-IFU) at a spatial resolution of ~250 pc and spectral resolution of 36 km s−1. Strong [O  iii ], Hα, [N  ii ] and [S  ii ] emission lines are detected over the entire field of view. The stellar kinematics trace circular rotation with a projected velocity amplitude of ±96 km s−1, a kinematic major axis in position angle of 11°, and an average velocity dispersion of 123 km s−1. To analyse the gas kinematics, we used aperture spectra, position–velocity diagrams and single/double Gaussian fits to the emission lines. All lines show two clear kinematic components: a rotating component that follows the stellar kinematics, and a larger-dispersion component, close to the systemic velocity (from which most of the [O  iii ] emission comes), mainly detected to the south-west. We interpret this second component as gas outflowing at ∼400 km s−1 in a compact (300 pc) ionization cone with a half-opening angle ≤40°. The counter-cone is probably obscured behind a dust lane. We estimate a mass outflow rate of 1.1 M |$\odot$| yr−1, 200 times larger than the estimated accretion rate on to the supermassive black hole, and a kinetic to radiative power ratio of 1.7 × 10−3. Bar-induced perturbations probably explain the remaining disturbances observed in the velocity field of the rotating gas component. [ABSTRACT FROM AUTHOR]

As part of a high-resolution observational study of feeding and feedback processes occurring in the vicinity of the active galactic nucleus in 40 galaxies, we observed the inner 3 |${^{\prime\prime}_{.}}$| 5 × 5 arcsec of the nearby spiral and Seyfert 2 galaxy UGC 2024 with the integral field unit of the Gemini-South Telescope. The observations enabled a study of the stellar and gas kinematics in this region at a spatial resolution of 0 |${^{\prime\prime}_{.}}$| 5 (218 pc), and a spectral resolution of 36  km s−1 over the wavelength range 4100–7300 Å. For the strongest emission-lines (H  β , [ |$\rm{O\,{\small III}}$| ] λ5007 Å, H  α , [ |$\rm{N\,{\small II}}$| ] λ6584 Å, and [ |$\rm{S\,{\small II}}$| ] λλ6717,6731 Å) we derived maps of the flux, radial velocity, and velocity dispersion. The flux distribution and kinematics of the [ |$\rm{O\,{\small III}}$| ] emission line are roughly symmetric around the nucleus: the radial velocity is close to systemic over the full field of view. The kinematics of the other strong emission lines trace both this systemic velocity component, and ordered rotation (with kinematic centre 0 |${^{\prime\prime}_{.}}$| 2 north-west of the nucleus). The stellar continuum morphology and kinematics are, however, asymmetrical around the nucleus. We interpret these unusual kinematics as the superposition of a component of gas rotating in the galaxy disc plus a 'halo' component of highly ionized gas. This halo either traces a quasi-spherical fountain with average radial velocity 200 km s−1, in which case the total nuclear outflow mass and momentum are 2 × 105 M⊙ and 4 × 107 M⊙ km s−1, respectively, or a dispersion supported halo created by a past nuclear starburst. [ABSTRACT FROM AUTHOR]

We observed the nuclear region of the galaxy NGC 1365 with the integral field unit of the Gemini Multi Object Spectrograph mounted on the GEMINI-South telescope. The field of view covers 13 ? 6 arcsec²(1173 ? 541 pc²) centred on the nucleus, at a spatial resolution of 52 pc. The spectral coverage extends from 5600 to 7000 Å, at a spectral resolution R = 1918. NGC 1365 hosts a Seyfert 1.8 nucleus, and exhibits a prominent bar extending out to 100 arcsec (9 kpc) from the nucleus. The field of view lies within the inner Lindblad resonance. Within this region, we found that the kinematics of the ionized gas (as traced by [O I], [N II], Ha, and [S II]) is consistent with rotation in the large-scale plane of the galaxy. While rotation dominates the kinematics, there is also evidence for a fan-shaped outflow, as found in other studies based on the [O III] emission lines. Although evidence for gas inflowing along nuclear spirals has been found in a few barred galaxies, we find no obvious signs of such features in the inner kiloparsec of NGC 1365. However, the emission lines exhibit a puzzling asymmetry that could originate from gas which is slower than the gas responsible for the bulk of the narrow-line emission. We speculate that it could be tracing gas which lost angular momentum, and is slowly migrating from the inner Lindblad resonance towards the nucleus of the galaxy. [ABSTRACT FROM AUTHOR]