ALBERT

Description: We present new maps of emission-line flux distributions and kinematics in both ionized (traced by H i and [Fe ii ] lines) and molecular (H 2 ) gas of the inner 0.7 x 0.7 kpc 2 of the galaxy NGC 4303, with a spatial resolution 40–80 pc and velocity resolution 90–150 km s – 1 obtained from near-IR integral field spectroscopy using the Very Large Telescope instrument SINFONI. The most prominent feature is a 200–250 pc ring of circumnuclear star-forming regions. The emission from ionized and molecular gas shows distinct flux distributions: while the strongest H i and [Fe ii ] emission comes from regions in the west side of the ring (ages ~ 4 Myr), the H 2 emission is strongest at the nucleus and in the east side of the ring (ages 〉 10 Myr). We find that regions of enhanced hot H 2 emission are anti-correlated with those of enhanced [Fe ii ] and H i emission, which can be attributed to post-starburst regions that do not have ionizing photons anymore but still are hot enough (2000 K) to excite the H 2 molecule. The line ratios are consistent with the presence of an active galactic nucleus at the nucleus. The youngest regions have stellar masses in the range 0.3–1.5 x 10 5  M and ionized and hot molecular gas masses of ~0.25–1.2 x 10 4 M and ~2.5–5 M , respectively. The stellar and gas velocity fields show a rotation pattern, with the gas presenting larger velocity amplitudes than the stars, with a deviation observed for the H 2 along the nuclear bar, where increased velocity dispersion is also observed, possibly associated with non-circular motions along the bar. The stars in the ring show smaller velocity dispersion than the surroundings, which can be attributed to a cooler dynamics due to their recent formation from cool gas.

Description: NGC 4258 is the galaxy with the most accurate (maser-based) determination for the mass of the supermassive black hole (SMBH) in its nucleus. In this work, we present a two-dimensional mapping of the stellar kinematics in the inner 3.0 arcsec 3.0 arcsec = 100 pc 100 pc of NGC 4258 using adaptive-optics observations obtained with the Near-Infrared Integral Field Spectrograph of the Gemini North telescope at an 0.11 arcsec (4 pc) angular resolution. The observations resolve the radius of influence of the SMBH, revealing an abrupt increase in the stellar velocity dispersion within 10 pc from the nucleus, consistent with the presence of an SMBH there. Assuming that the galaxy nucleus is in a steady state and that the velocity dispersion ellipsoid is aligned with a cylindrical coordinate system, we constructed a Jeans anisotropic dynamical model to fit the observed kinematics distribution. Our dynamical model assumes that the galaxy has axial symmetry and is constructed using the multi-Gaussian expansion method to parametrize the observed surface brightness distribution. The Jeans dynamical model has three free parameters: the mass of the central SMBH ( M • ), the mass–luminosity ratio ( k = M/L) of the galaxy and the anisotropy of the velocity distribution. We test two types of models: one with constant velocity anisotropy, and another with variable anisotropy. The model that best reproduces the observed kinematics was obtained considering that the galaxy has radially varying anisotropy, being the best-fitting parameters with 3 significance $M_\bullet =4.8^{+0.8}_{-0.9}\times 10^7\,{\rm M_{\odot }}$ and $\Gamma _k = 4.1^{+0.4}_{-0.5}$ . This value for the mass of the SMBH is just 25 per cent larger than that of the maser determination and 50 per cent larger that a previous stellar dynamical determination obtained via Schwarzschild models for long-slit data that provides an SMBH mass 15 per cent lower than the maser value.

Description: We present near-infrared emission-line flux distributions, excitation and kinematics, as well as stellar kinematics, of the inner 520  x  520 pc 2 of the Seyfert 2 galaxy NGC 5929. The observations were performed with Gemini's Near-Infrared Integral Field Spectrograph (NIFS) at a spatial resolution of ~20 pc and spectral resolution of 40 km s – 1 in the J and K l bands. The flux distributions of H 2 , [Fe ii ], [P ii ] and H recombination lines are extended over most of the field of view, with the highest intensity levels observed along PA = 60/240°, and well correlated with the radio emission. The H 2 and [Fe ii ] line emission originated in thermal processes, mainly due to heating of the gas by X-rays from the central active galactic nucleus (AGN). The contribution of shocks due to the radio jet is observed at locations co-spatial with the radio hotspots at 0.50 arcsec north-east and 0.60 arcsec south-west of the nucleus, as evidenced by the emission-line ratio and gas kinematics. The stellar kinematics shows rotation with an amplitude at 250 pc from the nucleus of ~200 km s – 1 after correcting for the inferred inclination of 18.3°. The stellar velocity dispersion obtained from the integrated K -band spectrum is *  = 133 ± 8 km s – 1 , which implies a mass for the supermassive black hole of $M_\bullet = 5.2^{1.6}_{-1.2} \times 10^7\,{\rm M_{{\odot }}}$ , using the M • – * relation. The gas kinematics present three components: (1) gas in the plane of the galaxy in counter-rotation relative to the stars; (2) an outflow perpendicular to the radio jet that seems to be due to an equatorial AGN outflow; and (3) turbulence of the gas observed in association with the radio hotspots, supporting an interaction of the radio jet with the gas of the disc. We estimated the masses of ionized gas and warm molecular gas to be ~1.3  x  10 6 M and ~470 M , respectively.

Description: We present two-dimensional gaseous kinematics of the inner 1.2  x  1.8 kpc 2 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 ( $\dot{M}_{{\rm out}}$ ) is between 1.9  x 10 –3 and 6.9  x 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   1.3  x 10 –2  M  yr –1 .

Description: We present a two-dimensional analysis of the gaseous excitation and kinematics of the inner 2.5 1.7 kpc 2 of the low-ionization nuclear emission-line region (LINER)/Seyfert 1 galaxy Arp 102B, from optical spectra obtained with the Gemini Multi-Object Spectrograph Integral Field Unit on the Gemini North telescope at a spatial resolution of 250 pc. Emission-line flux maps show the same two-armed nuclear spiral we have discovered in previous observations with the Hubble Space Telescope Advanced Camera for Surveys. One arm reaches 1 kpc to the east and the other 500 pc to the west, with an 8.4 GHz Very Large Array bent radio jet correlating with the former. Gas excitation along the arms is low, with line ratios typical of LINERs, and which rule out gas ionization by stars. The gas density is highest (500–900 cm –3 ) at the nucleus and in the northern border of the east arm, at a region where the radio jet seems to be deflected. Centroid velocity maps suggest that most gas is in rotation in an inclined disc with line of nodes along position angle 88°, redshifts to the west and blueshifts to the east, with lower blueshifts correlated with the eastern arm and radio jet. This correlation suggests that the jet is interacting with gas in the disc. This interaction is supported by the gas excitation as a function of distance from the nucleus, which requires the contribution from shocks. Channel maps show blueshifts but also some redshifts at the eastern arm and jet location which can be interpreted as originated in the front and back walls of an outflow pushed by the radio jet, suggesting also that the outflow is launched close to the plane of the sky. Principal Component Analysis applied to our data supports this interpretation. We estimate a mass outflow rate along the east arm of 0.26-0.32 M yr – 1 (depending on the assumed outflow geometry), which is between one and two orders of magnitude higher than the mass accretion rate to the active nucleus, implying that there is mass-loading of the nuclear outflow from circumnuclear gas. The power of this outflow is 0.06–0.3 per cent L bol . We propose a scenario in which gas has been recently captured by Arp 102B in an interaction with Arp 102A, settling in a disc rotating around the nucleus of Arp 102B and triggering its nuclear activity. A nuclear jet is pushing the circumnuclear gas, giving origin to the nuclear arms. A blueshifted emitting gas knot is observed at 300 pc southeast from the nucleus and can be interpreted as another (more compact) outflow, with a possible counterpart to the northwest.

Description: We map the kinematics of the inner (200 pc) narrow-line region (NLR) of the Seyfert 2 galaxy NGC 1068 using the instrument Near-infrared Integral Field Spectrograph and adaptive optics at the Gemini North telescope. Channel maps and position–velocity diagrams are presented at a spatial resolution of 8 pc and spectral resolution ~5300 in the emission lines [Fe ii ] 1.644 μm, H 2 2.122 μm and Br. The [Fe ii ] emission line provides a better coverage of the NLR outflow than the previously used [O iii ] 5007 emission line, extending beyond the area of the bipolar cone observed in Br and [O iii ]. This is mainly due to the contribution of the redshifted channels to the north-east of the nucleus, supporting its origin in a partial ionized zone with additional contribution from shocks of the outflowing gas with the galactic disc. We modelled the kinematics and geometry of the [Fe ii ] emitting gas finding good agreement with the data for outflow models with conical and lemniscate (or hourglass) geometry. We calculate a mass outflow rate of $1.9^{+2}_{-1}$  M  yr –1 but a power for the outflow of only 0.08 per cent L Bol . The molecular (H 2 ) gas kinematics is completely distinct from that of [Fe ii ] and Br, showing radial expansion in an off-centred ~100 pc radius ring in the galaxy plane. The expansion velocity decelerates from 200 km s –1 in the inner border of the ring to approximately zero at the outer border where our previous studies found a 10 Myr stellar population.

Description: We have mapped the emission-line flux distributions and ratios as well as the gaseous kinematics of the inner 450 pc radius of the type 1 Seyfert galaxy Mrk 766 using integral field near-infrared J - and K l -band spectra obtained with the Gemini Near Infrared Integral Field Spectrograph at a spatial resolution of 60 pc and velocity resolution of 40 km s –1 . Emission-line flux distributions in ionized and molecular gas extend up to 300 pc from the nucleus. Coronal [S ix ] 1.2523 μm line emission is resolved, being extended up to 150 pc from the nucleus. At the highest flux levels, the [Fe ii ] 1.257 μm line emission is most extended to the south-east, where a radio jet has been observed. The emission-line ratios [Fe ii ] 1.2570 μm/Paβ and H 2 2.1218 μm/Br show a mixture of Starburst and Seyfert excitation; the Seyfert excitation dominates at the nucleus, to the north-west and in an arc-shaped region between 0.2 and 0.6 arcsec to the south-east at the location of the radio jet. A contribution from shocks at this location is supported by enhanced [Fe ii ]/[P ii ] line ratios and increased [Fe ii ] velocity dispersion. The gas velocity field is dominated by rotation that is more compact for H 2 than for Paβ, indicating that the molecular gas has a colder kinematics and is located in the galaxy plane. There is about 10 3 M of hot H 2 , implying 10 9 M of cold molecular gas. At the location of the radio jet, we observe an increase in the [Fe ii ] velocity dispersion (150 km s –1 ), as well as both blueshift and redshifts in the channel maps, supporting the presence of an outflow there. The ionized gas mass outflow rate is estimated to be 10 M  yr –1 , and the power of the outflow 0.08 L bol .

Description: We have used optical Integral Field Spectroscopy in order to map the star formation history of the inner kiloparsec of the post-starburst quasar (PSQ) J0330–0532 and to map its gas and stellar kinematics as well as the gas excitation. PSQs are hypothesized to represent a stage in the evolution of galaxies in which the star formation has been recently quenched due to the feedback of the nuclear activity, as suggested by the presence of the post-starburst population at the nucleus. We have found that the old stellar population (age ≥ 2.5 Gyr) dominates the flux at 5100 Å in the inner 0.26 kpc, while both the post-starburst (100 Myr ≤ age 〈2.5 Gyr) and starburst (age 〈100 Myr) components dominate the flux in a circumnuclear ring at 0.5 kpc from the nucleus. With our spatially resolved study we have not found any post-starburst stellar population in the inner 0.26 kpc. On the other hand, we do see the signature of AGN feedback in this region, which does not reach the circumnuclear ring where the post-starburst population is observed. We thus do not support the quenching scenario for the PSQ J0330–0532. In addition, we have concluded that the strong signature of the post-starburst population in larger aperture spectra (e.g. from Sloan Digital Sky Survey) is partially due to the combination of the young and old age components. Based on the M BH – star relationship and the stellar kinematics we have estimated a mass for the supermassive black hole of 1.48 ± 0.66 10 7 M .

Description: We present two-dimensional stellar and gaseous kinematics of the inner 0.8 1.1 kpc 2 of the LINER/Seyfert 1 galaxy NGC 7213, from optical spectra obtained with the Gemini Multi-Object Spectrograph integral field spectrograph on the Gemini South telescope at a spatial resolution of  60 pc. The stellar kinematics shows an average velocity dispersion of 177 km s –1 , circular rotation with a projected velocity amplitude of 50 km s –1 and a kinematic major axis at a position angle of –4° (west of north). From the average velocity dispersion we estimate a black hole mass of M BH  = 8  $_{-6}^{+16}\times$ 10 7 M . The gas kinematics is dominated by non-circular motions, mainly along two spiral arms extending from the nucleus out to 4 arcsec (280 pc) to the NW and SE, that are cospatial with a nuclear dusty spiral seen in a structure map of the nuclear region of the galaxy. The projected gas velocities along the spiral arms show blueshifts in the far side and redshifts in the near side, with values of up to 200 km s –1 . This kinematics can be interpreted as gas inflows towards the nucleus along the spiral arms if the gas is in the plane of the galaxy. We estimate the mass inflow rate using two different methods. The first is based of the observed velocities and geometry of the flow, and gives a mass inflow rate in the ionized gas of 7 10 –2 M yr –1 . In the second method, we calculate the net ionized gas mass flow rate through concentric circles of decreasing radii around the nucleus resulting in mass inflow rates ranging from 0.4 M yr –1 at 300 pc down to 0.2 M yr –1 at 100 pc from the nucleus. These rates are larger than necessary to power the active nucleus.

Description: We perform an exploratory study of the physical properties of accretion flows and jets in low-luminosity active galactic nuclei (LLAGNs) by modelling the spectral energy distributions (SEDs) of 12 LLAGNs in low-ionization nuclear emission-line regions (LINERs). These SEDs we constructed from high-resolution radio, X-ray and optical/ultraviolet (UV) observations of the immediate vicinity of the black hole. We adopt a coupled accretion-jet model comprising an inner advection-dominated accretion flow (ADAF) and an outer standard thin disc. We present best-fitting models in which either the ADAF or the jet dominates the X-ray emission. Six sources in our sample display an optical–UV excess with respect to ADAF and jet models; this excess can be explained as emission from the truncated disc with transition radii 30–225 R S in four of them. In almost all sources the optical emission can also be attributed to unresolved, old stellar clusters with masses ~10 7 –10 8 M . We find evidence for a correlation between the accretion rate and jet power and an anticorrelation between the radio loudness and the accretion rate. We confirm previous findings that the radio emission is severely underpredicted by ADAF models and explained by the relativistic jet. We find evidence for a non-linear relation between the X-ray and bolometric luminosities and a slight IR excess in the average model SED compared to that of quasars. We suggest that the hardness of the X-ray spectrum can be used to identify the X-ray emission mechanism and discuss directions for progress in understanding the origin of the X-rays.