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We investigate the formation and evolution of z = 0 massive compact galaxies (MCGs) in the IllustrisTNG cosmological simulation. We found that, as in observations, MCGs are mainly old (median age ∼10.8 Gyr), have supersolar metallicities (median log  Z /Z⊙ ∼ 0.35), and are α-enhanced (median [α/Fe] ∼ 0.25). The age distribution extends to younger ages, however, and a few MCGs are as young as ∼7 Gyr. In general, MCGs assemble their mass early and accrete low angular momentum gas, significantly increasing their mass while growing their size much slower. A small fraction of MCGs follow another evolutionary path, going through a compaction event, with their sizes shrinking by 40 per cent or more. The accretion of low angular momentum gas leads to enhanced supermassive black hole (SMBH) growth, and MCGs reach the threshold SMBH mass of |$\log M_\mathrm{BH}\sim 10^{8.5}\ \mathrm{ M}_\odot$| – when kinetic active galactic nucleus feedback kicks in and quenches the galaxy – earlier than non-compact galaxies. Comparing MCGs to a sample of median-sized quiescent galaxies matched in effective velocity dispersion, we find that their accretion histories are very different. 71 per cent of MCGs do not merge after quenching compared to 37 per cent of median-sized quiescent galaxies. Moreover, tracing these populations back in time, we find that at least a third of median-sized quiescent galaxies do not have a compact progenitor, underscoring that both dry mergers and progenitor bias effects are responsible for the differences in the kinematics and stellar population properties of MCGs and median-sized quiescent galaxies. [ABSTRACT FROM AUTHOR]

We characterized the kinematics, morphology, and stellar population (SP) properties of a sample of massive compact quiescent galaxies (MCGs, |$10\, \lesssim \, \log M_\star$| /M |$_\odot \, \lesssim \, 11$| and r e ∼ 1–3 kpc) in the MaNGA Survey, with the goal of constraining their formation, assembly history, and assessing their relation with non-compact quiescent galaxies. We compared their properties with those of a control sample of median-sized quiescent galaxies (r e ∼ 4–8 kpc) with similar effective velocity dispersions. MCGs have elevated rotational support, as evidenced by a strong anticorrelation between the Gauss–Hermite moment h 3 and V / σ. In contrast, 30 |${{\ \rm per\ cent}}$| of control sample galaxies (CSGs) are slow rotators, and fast-rotating CSGs generally show a weak h 3– V / σ anticorrelation. MCGs and CSGs have similar ages, but MCGs are more metal-rich and α -enhanced. Both MCGs and CSGs have shallow negative metallicity gradients and flat [ α /Fe] gradients. On average, MCGs and CSGs have flat age gradients, but CSGs have a significantly larger dispersion of gradient values. The kinematics and SP properties of MCGs suggest that they experienced highly dissipative gas-rich events, such as mergers, followed by an intense, short, and centrally concentrated burst of star formation, between 4 and 10 Gyr ago (z ∼ 0.4–2), and had a quiet accretion history since then. This sequence of events might be analogous to, although less extreme than, the compaction events that formed compact quiescent galaxies at z  ∼ 2. The small sizes of MCGs, and the high efficiency and short duration of their last star formation episode suggest that they are descendants of compact post-starburst galaxies. [ABSTRACT FROM AUTHOR]

We use optical spectra from the inner 1.8×2.5 kpc² of the Seyfert 2 galaxy NGC1358, obtained with the GMOS integral field spectrograph on the Gemini South telescope at a spatial resolution of ≈165 pc, to assess the feeding and feedback processes in this nearby active galaxy. Five gaseous kinematical components are observed in the emission line profiles. One of the components is present in the entire field-of-view and we interpret it as due to gas rotating in the disc of the galaxy. Three of the remaining components we interpret as associated with active galactic nucleus (AGN) feedback: a compact unresolved outflow in the inner 1 arcsec and two gas clouds observed at opposite sides of the nucleus, which we propose have been ejected in a previous AGN burst. The disc component velocity field is strongly disturbed by a large-scale bar. The subtraction of a velocity model combining both rotation and bar flows reveals three kinematic nuclear spiral arms: two in inflow and one in outflow. We estimate the mass inflow rate in the inner 180 pc obtaining Min ≈1.5×10-2⊙ yr-1, about 160 times larger than the accretion rate necessary to power this AGN. [ABSTRACT FROM AUTHOR]

Ionized gas outflows driven by active galactic nuclei (AGN) are ubiquitous in high-luminosity AGN with outflow speeds apparently correlated with the total bolometric luminosity of the AGN. This empirical relation and theoretical work suggest that in the range Lbol ~ 1043-45 erg s-1 there must exist a threshold luminosity above which the AGN becomes powerful enough to launch winds that will be able to escape the galaxy potential. In this paper, we present pilot observations of two AGN in this transitional range that were taken with the Gemini North Multi-Object Spectrograph integral field unit (IFU). Both sources have also previously been observed within the Sloan Digital Sky Survey-IV (SDSS) Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey. While the MaNGA IFU maps probe the gas fields on galaxy-wide scales and show that some regions are dominated by AGN ionization, the new Gemini IFU data zoom into the centre with four times better spatial resolution. In the object with the lower Lbol we find evidence of a young or stalled biconical AGN-driven outflow where none was obvious at the MaNGA resolution. In the object with the higher Lbol we trace the large-scale biconical outflow into the nuclear region and connect the outflow from small to large scales. These observations suggest that AGN luminosity and galaxy potential are crucial in shaping wind launching and propagation in low-luminosity AGN. The transition from small and young outflows to galaxy-wide feedback can only be understood by combining large-scale IFU data that trace the galaxy velocity field with higher resolution, small-scale IFU maps. [ABSTRACT FROM AUTHOR]

We present two-dimensional gaseous kinematics of the inner 1.2 × 1.8 kpc2 of the Seyfert 2 galaxy NGC 3081, from optical spectra (5600-7000 Å) obtained with the Gemini Multi Object Spectrograph integral field spectrograph on the Gemini North telescope at a spatial resolution of ≈100 pc.We have identified two components in the line emitting gas. A narrower component (full width at half-maximum, FWHM ≈ 60-100 km s-1), which appears to be gas in the galaxy disc, and which shows a distorted rotation pattern, is observed over the whole field of view. A broader component (FWHM ≈ 150-250 km s-1) is present in the inner ≈2 arcsec (200 pc) and shows blueshifts and redshifts in the near and far sides of the galaxy, respectively, consistent with a bipolar outflow. Assuming this to be the case, we estimate that the mass outflow rate in ionized gas(Mout) is between 1.9 ×10-3 and 6.9 ×10-3 M☉ yr-1. The subtraction of a rotation model from the narrower component velocity field reveals a pattern of excess blueshifts of ≈50 km s-1 in the far side of the galaxy and similar excess redshifts in the near side, which are cospatial with a previously known nuclear bar.We interpret these residuals as due to gas following non-circular orbits in the barred potential. Under the assumption that these motions may lead to gas inflows, we estimate an upper limit for the mass inflow rate in ionized gas of ϕ ≈ 1.3 ×10-2 M☉ yr-1. [ABSTRACT FROM AUTHOR]

We analyse optical data cubes of the inner kiloparsec of 30 local (z ≤ 0.02) active galactic nucleus (AGN) hosts that our research group, AGNIFS, has collected over the past decade via observations with the integral field units of the Gemini Multi-Object Spectrographs. Spatial resolutions range between 50 and 300 pc and spectral coverage is from 4800 or 5600 to 7000 Å, at velocity resolutions of ≈50  |$\rm ~km~s^{-1}$|⁠. We derive maps of the gas excitation and kinematics, and determine the AGN ionization axis – which has random orientation relative to the galaxy – and the kinematic major axes of the emitting gas. We find that rotation dominates the gas kinematics in most cases, but is disturbed by the presence of inflows and outflows. Outflows have been found in 21 nuclei, usually along the ionization axis. The gas velocity dispersion is traced by W 80 (velocity width encompassing 80 per cent of the line flux), adopted as a tracer of outflows. In seven sources, W 80 is enhanced perpendicularly to the ionization axis, indicating lateral expansion of the outflow. We have estimated mass-outflow rates |$\dot{M}$| and powers |$\dot{E}$|⁠ , finding median values of |$\log \, [\dot{M}/({\rm \, M_\odot \, yr^{-1}})]=-2.1_{-1.0}^{+1.6}$| and |$\log \, [\dot{E}/({\rm \, erg\, s^{-1}})]=38.5_{-0.9}^{+1.8}$|⁠ , respectively. Both quantities show a mild correlation with the AGN luminosity (L AGN). |$\dot{E}$| is of the order of 0.01 L AGN for four sources, but much lower for the majority (nine) of the sources, with a median value of |$\log \, [\dot{E}/L_{\rm AGN} ]=-5.34_{-0.9}^{+3.2}$|⁠ , indicating that typical outflows in the local Universe are unlikely to significantly impact their host galaxy evolution. [ABSTRACT FROM AUTHOR]

We present optical integral field spectroscopy - obtained with the Gemini Multi-Object Spectrograph - of the inner 4.0 × 5.8 kpc2 of the narrow line radio galaxy 3C 33 at a spatial resolution of 0.58 kpc. The gas emission shows three brightest structures: a strong knot of nuclear emission and two other knots at ≈1.4 kpc south-west and north-east of the nucleus along the ionization axis. We detect two kinematic components in the emission lines profiles, with a 'broader component' (with velocity dispersion σ ≥ 150 km s--1 )being dominant within an ~1 kpc wide strip ('the nuclear strip') running from the south-east to the north-west, perpendicular to the radio jet, and a narrower component (σ ≤ 100 km s--1 ) dominating elsewhere. Centroid velocity maps reveal a rotation pattern with velocity amplitudes reaching ~± 350 km s--1 in the region dominated by the narrow component, while residual blueshifts and redshifts relative to rotation are observed in the nuclear strip, where we also observe the highest values of the [NII]/Hα, [SII]/Hα and [OI]/Hα line ratios, and an increase of the gas temperature (~18 000 K), velocity dispersion and electron density (~500 cm--3 ). We interpret these residuals and increased line ratios as due to a lateral expansion of the ambient gas in the nuclear strip due to shocks produced by the passage of the radio jet. The effect of this expansion in the surrounding medium is very small, as its estimated kinetic power represents only 2.6 × 10--5 - 3.0 × 10--5 of the AGN bolometric luminosity. A possible signature of inflow is revealed by an increase in the [OI]/Hα ratio values and velocity dispersions in the shape of two spiral arms extending to 2.3 kpc north-east and south-west from the nucleus. [ABSTRACT FROM AUTHOR]

Galaxy mergers are central to our understanding of galaxy formation, especially within the context of hierarchical models. Besides having a large impact on the star formation history, mergers are also able to influence gas motions at the centre of galaxies and trigger an active galactic nucleus (AGN). In this paper, we present a case study of the Seyfert galaxy NGC 2992, which together with NGC 2993 forms the early-stage merger system Arp 245. Using Gemini Multi-Object Spectrograph integral field unit data from the inner 1.1 kpc of the galaxy, we were able to spatially resolve the stellar populations, the ionization mechanism, and kinematics of ionized gas. From full spectral synthesis, we found that the stellar population is primarily composed by old metal-rich stars (t ≥ 1.4 Gyr, Z ≥ 2.0 Z⊙), with a contribution of at most 30 per cent of the light from a young and metal-poor population (t ≤ 100 Myr, Z ≤ 1.0 Z⊙). We detect H α and H β emission from the broad-line region with a full width at half-maximum of ∼2000  |$\rm km\, s^{-1}$|⁠. The narrow-line region kinematics presents two main components: one from gas orbiting the galaxy disc and a blueshifted (velocity ≈ −200  |$\rm km\, s^{-1}$|⁠) outflow, possibly correlated with the radio emission, with mass outflow rate of ∼2 M⊙ yr−1 and a kinematic power of ∼2 × 1040 erg s−1 (⁠|$\dot{E}_{\mathrm{ out}}$| / L bol ≈ 0.2 per cent). We also show even though the main ionization mechanism is the AGN radiation, ionization by young stars and shocks may also contribute to the emission line ratios presented in the innermost region of the galaxy. [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]

NGC 3393, a nearby Seyfert 2 galaxy with nuclear radio jets, large-scale and nuclear bars, and a posited secondary supermassive black hole, provides an interesting laboratory to test the physics of inflows and outflows. Here we present and analyse the molecular gas [ALMA observations of CO J:2-1 emission over a field of view (FOV) of 45 arcsec × 45 arcsec, at 0 $${^{\prime\prime}_{.}}$$ 56 (143 pc) spatial and 5 km s−1 spectral resolution), ionized gas and stars (GEMINI–GMOS/IFU; over an FOV of 4 arcsec × 5 arcsec, at 0 $${^{\prime\prime}_{.}}$$ 62 (159 pc) spatial and 23 km s−1 spectral resolution) in NGC 3393. The ionized gas emission, detected over the complete GEMINI–GMOS FOV, has three identifiable kinematic components. A narrow (σ < 115 km s−1) component present in the complete FOV, which is consistent with rotation in the galaxy disc. A broad (σ > 115 km s−1) redshifted component, detected near the NE and SW radio lobes; which we interpret as a radio jet-driven outflow. And a broad (σ > 115 km s−1) blueshifted component that shows high velocities in a region perpendicular to the radio jet axis; we interpret this as an equatorial outflow. The CO J:2-1 emission is detected in spiral arms on 5–20 arcsec scales, and in two disturbed circumnuclear regions. The molecular kinematics in the spiral arms can be explained by rotation. The highly disturbed kinematics of the inner region can be explained by perturbations induced by the nuclear bar and interactions with the large scale bar. We find no evidence for, but cannot strongly rule out, the presence of the posited secondary black hole. [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]