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We present the hot molecular and warm ionized gas kinematics for 33 nearby (0.001 ≲ z ≲ 0.056) X-ray selected active galaxies using the H |$_2\, 2.1218\, \mu$| m and Br γ emission lines observed in the K band with the Gemini near-infrared integral field spectrograph. The observations cover the inner 0.04–2 kpc of each active galactic nucleus at spatial resolutions of 4–250 pc with a velocity resolution of σinst ≈ 20  |${\rm km\, s^{-1}}$|⁠. We find that 31 objects (94 per cent) present a kinematically disturbed region (KDR) seen in ionized gas, while such regions are observed in hot molecular gas for 25 galaxies (76 per cent). We interpret the KDR as being due to outflows with masses of 102–107 and 100–104 M⊙ for the ionized and hot molecular gas, respectively. The ranges of mass-outflow rates (⁠|$\dot{M}_{\rm out}$|⁠) and kinetic power (⁠|$\dot{E}_{\rm K}$|⁠) of the outflows are 10−3–101 M⊙ yr−1 and ∼1037–1043 erg s−1 for the ionized gas outflows, and 10−5–10−2 M⊙ yr−1 and 1035–1039 erg s−1 for the hot molecular gas outflows. The median coupling efficiency in our sample is |$\dot{E}_{\mathrm{K}}/L_{\rm bol}\approx 1.8\times 10^{-3}$| and the estimated momentum fluxes of the outflows suggest they are produced by radiation-pressure in low-density environment, with possible contribution from shocks. [ABSTRACT FROM AUTHOR]

We study the gas distribution and kinematics of the inner kpc of six moderately luminous (43.43 ≤ log  L bol ≤ 44.83) nearby (0.004 ≤ z ≤ 0.014) Seyfert galaxies observed with the Near-infrared Integral Field Spectrograph (NIFS) in the J (⁠|$1.25\,\mu$| m) and K (⁠|$2.2\,\mu$| m) bands. We analyse the most intense emission lines detected on these spectral wavebands: [Fe  ii ]  |$1.2570\, \mu$| m and Paβ, which trace the ionized gas in the partially and fully ionized regions, and |$\mathrm{ H}_2 \ 2.1218\, \mu$| m, which traces the hot (∼2000 K) molecular gas. The dominant kinematic component is rotation in the disc of the galaxies, except for the ionized gas in NGC 5899 that shows only weak signatures of a disc component. We find ionized gas outflow in four galaxies, while signatures of H2 outflows are seen in three galaxies. The ionized gas outflows display velocities of a few hundred km s−1, and their mass outflow rates are in the range 0.005–12.49 M⊙ yr−1. Their kinetic powers correspond to 0.005–0.7 per cent of the active galactic nuclei (AGN) bolometric luminosities. Besides rotation and outflows signatures in some cases, the H2 kinematics also reveals inflows in three galaxies. The inflow velocities are 50–80 km s−1 and the mass inflow rates are in the range 1–9 × 10−4 M⊙ yr−1 for hot molecular gas. These inflows might be only the hot skin of the total inflowing gas, which is expected to be dominated by colder gas. The mass inflow rates are lower than the current accretion rates to the AGN, and the ionized outflows are apparently disturbing the gas in the inner kpc. [ABSTRACT FROM AUTHOR]

The merger remnant NGC 34 is a local luminous infrared galaxy (LIRG) hosting a nuclear starburst and a hard X-ray source associated with a putative, obscured Seyfert 2 nucleus. In this work, we use adaptive optics assisted near-infrared (NIR) integral field unit observations of this galaxy to map the distribution and kinematics of the ionized and molecular gas in its inner |$\mathrm{1.2\, kpc \times 1.2\, kpc}$|⁠ , with a spatial resolution of 70 pc. The molecular and ionized gas kinematics is consistent with a disc with projected major axis along a mean PA = −9 |${_{.}^{\circ}}$| 2 ± 0 |${_{.}^{\circ}}$| 9. Our main findings are that NGC 34 hosts an AGN and that the nuclear starburst is distributed in a circumnuclear star formation ring with inner and outer radii of ≈ 60 and 180 pc, respectively, as revealed by maps of the |$\mathrm{[Fe\, {\small {II}}] / Pa\,\beta }$| and H2/Br  γ emission-line ratios, and corroborated by PCA tomography analysis. The spatially resolved NIR diagnostic diagram of NGC 34 also identifies a circumnuclear structure dominated by processes related to the stellar radiation field and a nuclear region where |$[\rm Fe\, {\small {II}}]$| and H2 emissions are enhanced relative to the hydrogen recombination lines. We estimate that the nuclear X-ray source can account for the central H2 enhancement and conclude that |$[\rm Fe\, {\small {II}}]$| and H2 emissions are due to a combination of photoionization by young stars, excitation by X-rays produced by the AGN and shocks. These emission lines show nuclear, broad, blueshifted components that can be interpreted as nuclear outflows driven by the AGN. [ABSTRACT FROM AUTHOR]

In order to gauge the role that active galactic nuclei play in the evolution of galaxies via the effect of kinetic feedback in nearby QSO 2's (z ∼ 0.3), we observed eight such objects with bolometric luminosities |$L_{bol} \sim 10^{46}\rm {erg\, s^{-1}}$| using Gemini Multi-Object Spectrograph-integral field units. The emission lines were fitted with at least two Gaussian curves, the broadest of which we attributed to gas kinetically disturbed by an outflow. We found that the maximum extent of the outflow ranges from ∼1 to 8 kpc, being |${\sim }\, 0.5\, {\pm }\, 0.3$| times the extent of the [ |$\mathrm{O\,{\small III}}$| ] ionized gas region. Our ' default ' assumptions for the gas density (obtained from the [ |$\mathrm{S\,{\small II}}$| ] doublet) and outflow velocities resulted in peak mass outflow rates of |$\dot{M}_{\mathrm{ out}}^{{\tt def}}\sim$|  3–30  |$\rm {M_{\odot }}\, yr^{-1}$| and outflow power of |$\dot{E}_{\mathrm{ out}}^{{\tt \mathrm{ def}}}\sim \, 10^{41}$| – |$10^{43}\, \mathrm{erg\, s^{-1}}$|⁠. The corresponding kinetic coupling efficiencies are |$\varepsilon _f^{{\tt def}}=\dot{E}_{\mathrm{ out}}^{{\tt def}}/L_{\mathrm{ bol}}\, \sim 7\times 10^{-4}$| –0.5 per cent, with the average efficiency being only 0.06 per cent (0.01 per cent median), implying little feedback powers from ionized gas outflows in the host galaxies. We investigated the effects of varying assumptions and calculations on |$\dot{M}_{\mathrm{ out}}$| and |$\dot{E}_{\mathrm{ out}}$| regarding the ionized gas densities, velocities, masses, and inclinations of the outflow relative to the plane of the sky, resulting in average uncertainties of 1 dex. In particular, we found that better indicators of the [ |$\mathrm{O\,{\small III}}$| ] emitting gas density than the default [ |$\mathrm{S\,{\small II}}$| ] line ratio, such as the [ |$\mathrm{Ar\,{\small IV}}$| ] λλ4711,40 line ratio, result in almost an order of magnitude decrease in the ε f . [ABSTRACT FROM AUTHOR]

We investigate the impact of the diffuse ionized gas (DIG) on abundance determinations in star-forming (SF) galaxies. The DIG is characterized using the H α equivalent width (W H α). From a set of 1 409 SF galaxies from the Mapping Nearby Galaxies at APO (MaNGA) survey, we calculate the fractional contribution of the DIG to several emission lines using high- S / N data from SF spaxels (instead of using noisy emission-lines in DIG-dominated spaxels). Our method is applicable to spectra with observed W H α ≳ 10 Å (which are not dominated by DIG emission). Since the DIG contribution depends on galactocentric distance, we provide DIG-correction formulae for both entire galaxies and single aperture spectra. Applying those to a sample of |$\, \gt 90\, 000$| SF galaxies from the Sloan Digital Sky Survey, we find the following. (1) The effect of the DIG on strong-line abundances depends on the index used. It is negligible for the ([O  iii ]/H β)/([N  ii ]/H α) index, but reaches ∼0.1 dex at the high-metallicity end for [N  ii ]/H α. (2) This result is based on the ∼kpc MaNGA resolution, so the real effect of the DIG is likely greater. (3) We revisit the mass–metallicity–star formation rate (SFR) relation by correcting for the DIG contribution in both abundances and SFR. The effect of DIG removal is more prominent at higher stellar masses. Using the [N  ii ]/Hα index, O/H increases with SFR at high stellar mass, contrary to previous claims. [ABSTRACT FROM AUTHOR]