arXiv subjects

H. R. Schmitt

Publications and source records attributed to H. R. Schmitt.

At least 19 recordsLinked to original sources

arXiv2026

Hot, Photoionized X-ray Gas in Two Luminous Type 2 Quasars: Chandra-HST Evidence for a Wind-Driven Sequence

We present new Chandra/ACIS-S imaging spectroscopy of two luminous type 2 quasars, FIRST J120041.4+314745 ($z$=0.116) and 2MASX J13003807+5454367 ($z$=0.088), and compare their X-ray emission with Hubble Space Telescope [O III]$λ$5007 morphologies and kinematics. Both systems show kiloparsec-scale soft X-ray emission. In FIRST J120041, the X-ray morphology is clumpy and closely follows the [O III] structures, with surface-brightness peaks co-spatial with the highest [O III] velocities (600-750 km s$^{-1}$) and broadest line widths ($\sim$1700 km s$^{-1}$). In 2MASX J130038, the X-ray emission is centrally concentrated and weakly correlated with rotational [O III] kinematics. Spectral modeling indicates that photoionization dominates the soft X-rays in both quasars. The inferred hot-gas reservoirs are substantial, $M_{\rm x-ray}\sim4.5\times10^{8}M_\odot$ (FIRST J120041) and $M_{\rm x-ray}\sim1.8\times10^{8}M_\odot$ (2MASX J130038), exceeding the outflowing [O III] masses by factors of $\sim$4 and $\sim$16. In 2MASX J130038, we identify a tentative blueshifted Fe XXVI Ly$α$ line at $E_{\rm rest}=7.14\pm0.06$ keV ($v\sim7600$ km s$^{-1}$), consistent with a hot wind confined to the inner few hundred parsecs. Combining these results with a broader sample of twelve type 2 quasars, we argue that luminous quasars evolve along a continuous feedback sequence regulated by progressive clearing of circumnuclear gas. As AGN radiation and winds pierce the surrounding medium, systems transition from heavily enshrouded, compact configurations to phases where the X-ray and [O III] components strongly couple and, eventually, to energetically dominant outflows. FIRST J120041 and 2MASX J130038 represent two points along this sequence, tracing the emergence and growth of hot winds as primary drivers of quasar-scale feedback.

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arXiv2024

Hubble Space Telescope Observations of Nearby Type 1 Quasars. I. Characterisation of the Extended [O III] 5007Å Emission

We use the Hubble Space Telescope to analyse the extended [O III] 5007A emission in seven bright radio-quiet type 1 quasars (QSO1s), focusing on the morphology and physical conditions of their extended Narrow-Line Regions (NLRs). We find NLRs extending 3-9 kpc, with four quasars showing roughly symmetrical structures (b/a=1.2-1.5) and three displaying asymmetric NLRs (b/a=2.4-5.6). When included with type 1 and type 2 AGNs from previous studies, the sizes of the extended [O III] regions scale with luminosity as $R[O III] \sim L[O III]^{0.5}$, consistent with photoionisation. However, when analysed separately, type 1s exhibit a steeper slope ($γ=0.57\pm0.05$) compared to type 2 AGNs ($γ=0.48\pm0.02$). We use photoionisation modeling to estimate the maximum NLRs sizes, assuming a minimum ionisation parameter of $\log(U) = -3$, an ionising luminosity based on the $L[O III]$-derived bolometric luminosity, and a minimum gas number density $n_H \sim 100\,\text{cm}^{-3}$, assuming that molecular clouds provide a reservoir for the ionised gas. The derived sizes agree well with direct measurements for a sample of type 2 quasars, but are underestimated for the current sample of QSO1s. A better agreement is obtained for the QSO1s using bolometric luminosities derived from the 5100A continuum luminosity. Radial mass profiles for the QSO1s show significant extended mass in all cases, but with less [O III]-emitting gas near the central AGN compared to QSO2s. This may suggest that the QSO1s are in a later evolutionary stage than QSO2s, further past the blow-out stage.

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arXiv2024

Resolving Dual Active Galactic Nuclei with ~100 pc separation in MCG-03-34-64

We report the serendipitous multiwavelength discovery of a candidate dual black hole system with a separation of ~100 pc, in the gas-rich luminous infrared galaxy MCG-03-34-64 (z=0.016). Hubble Space Telescope/ACS observations show three distinct optical centroids in the [O III] narrow-band and F814W images. Subsequent analysis of Chandra/ACIS data shows two spatially-resolved peaks of equal intensity in the neutral Fe Ka (6.2-6.6 keV) band, while high-resolution radio continuum observations with the Very Large Array at 8.46 GHz (3.6 cm band) show two spatially-coincident radio peaks. Fast shocks as the ionizing source seem unlikely, given the energies required for production of Fe Ka. If confirmed, the separation of ~100 pc would represent the closest dual AGN reported to date with spatially-resolved, multiwavelength observations.

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arXiv2022

Tracking X-ray Outflows with Optical/IR Footprint Lines

We use Cloudy photoionisation models to predict the flux profiles for optical/IR emission lines that trace the footprint of X-ray gas, such as [Fe X] 6375A and [Si X] 1.43$μ$m. These are a subset of coronal lines, from ions with ionisation potential $\geq$ that of O VII, i.e., 138eV. The footprint lines are formed in gas over the same range in ionisation state as the H and He-like of O and Ne ions, which are also the source of X-ray emission lines. The footprint lines can be detected with optical and IR telescopes, such as the Hubble Space Telescope/STIS and James Webb Space Telescope/NIRSpec, and can potentially be used to measure the kinematics of the extended X-ray emission gas. As a test case, we use the footprints to quantify the properties of the X-ray outflow in the Seyfert 1 galaxy NGC 4151. To confirm the accuracy of our method, we compare our model predictions to the measured flux from archival STIS spectra and previous ground-based studies, and the results are in good agreement. We also use our X-ray footprint method to predict the mass profile for the X-ray emission-line gas in NGC 4151 and derive a total spatially-integrated X-ray mass of $7.8(\pm 2.1) \times 10^{5}~M_{\odot}$, in comparison to $5.4(\pm 1.1) \times 10^{5}~M_{\odot}$ measured from a Chandra X-ray analysis. Our results indicate that high-ionisation footprint emission lines in the optical and near-infrared can be used to accurately trace the kinematics and physical conditions of AGN ionised, X-ray emission-line gas.

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arXiv2021

Hubble Space Telescope [O III] Emission-Line Kinematics in Two Nearby QSO2s: A Case for X-ray Feedback

We present a dynamical study of the narrow-line regions in two nearby QSO2s. We construct dynamical models based on detailed photoionization models of the emission-line gas, including the effects of internal dust, to apply to observations of large-scale outflows from these AGNs. We use Mrk 477 and Mrk 34 in order to test our models against recent HST STIS observations of [O III] emission-line kinematics since these AGNs possess more energetic outflows than found in Seyfert galaxies. We find that the outflows within 500 pc are consistent with radiative acceleration of dusty gas, however, the outflows in Mrk 34 are significantly more extended and may not be directly accelerated by radiation. We characterize the properties of X-ray winds found from the expansion of [O III]-emitting gas close to the black hole. We show that such winds possess the kinetic energy density to disturb [O III] gas at 1.8 kpc, and have sufficient energy to entrain the [O III] clouds at 1.2 kpc. Assuming that the X-ray wind possesses the same radial mass distribution as the [O III] gas, we find that the peak kinetic luminosity for this wind is 2% of Mrk 34's bolometric luminosity, which is in the 0.5% - 5% range required by some models for efficient feedback. Our work shows that, although the kinetic luminosity as measured from [O III]-emitting gas is frequently low, X-ray winds may provide more than one order of magnitude higher kinetic power.

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arXiv2021

Gauging the effect of Supermassive Black Holes feedback on Quasar host galaxies

In order to gauge the role that active galactic nuclei (AGN) play in the evolution of galaxies via the effect of kinetic feedback in nearby QSO$\,$2's ($z\sim0.3$), we observed eight such objects with bolometric luminosities $L_{bol} \sim 10^{46}\rm{erg\,s^{-1}}$ using Gemini GMOS-IFU's. 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 $\sim$1 to 8 kpc, being ${\sim}\,0.5\,{\pm}\,0.3$ times the extent of the [O$\,$III] ionized gas region. Our `${\tt default}$' assumptions for the gas density (obtained from the {[S$\,$II] doublet) and outflow velocities resulted in peak mass outflow rates of $\dot{M}_{out}^{\tt defa}{\sim}\,3\,{-}\,30\,\rm{M_{\odot}}\,yr^{-1}$ and outflow power of $\dot{E}_{out}^{\tt defa}\sim\,10^{41}\,{-}\,10^{43}\,\mathrm{erg\,s^{-1}}$. The corresponding kinetic coupling efficiencies are $\varepsilon_f^{\tt defa}=\dot{E}_{out}^{\tt defa}/L_{bol}\,\sim7\times10^{-4}\,{-}\,0.5\,\%$, with the average efficiency being only $0.06\,\%$ ($0.01\,\%$ median), implying little feedback powers from ionized gas outflows in the host galaxies. We investigated the effects of varying assumptions and calculations on $\dot{M}_{out}$ and $\dot{E}_{out}$ regarding the ionized gas densities, velocities, masses and inclinations of the outflow relative to the plane of the sky, resulting in average uncertainties of one dex. In particular, we found that better indicators of the [O$\,$III] emitting gas density than the default [S$\,$II] line ratio, such as the [Ar$\,$IV]$λλ$4711,40 line ratio, result in almost an order of magnitude decrease in the $\varepsilon_f$.

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arXiv2020

Hubble Space Telescope Observations of [O~III] Emission in Nearby QSO2s: Physical Properties of the Ionised Outflows

We use Hubble Space Telescope (HST)/ Space Telescope Imaging Spectrograph (STIS) long-slit G430M and G750M spectra to analyse the extended [O~III] 5007A emission in a sample of twelve nearby (z < 0.12) luminous (L_bol > 1.6 x 10^45 erg s^-1) QSO2s. The purpose of the study is to determine the properties of the mass outflows of ionised gas and their role in AGN feedback. We measure fluxes and velocities as functions of radial distances. Using Cloudy models and ionising luminosities derived from [O~III] 5007A, we are able to estimate the densities for the emission-line gas. From these results, we derive masses of [O~III]-emitting gas, mass outflow rates, kinetic energies, kinetic luminosities, momenta and momentum flow rates as a function of radial distance for each of the targets. For the sample, masses are several times 10^3 - 10^7 solar masses and peak outflow rates are 9.3 x 10^-3 Msun/yr to 10.3 Msun/yr. The peak kinetic luminosities are 3.4 x 10^-8 to 4.9 x 10^-4 of the bolometric luminosity, which does not approach the 5.0 x 10^-3 - 5.0 x 10^-2 range required by some models for efficient feedback. For Mrk 34, which has the largest kinetic luminosity of our sample, in order to produce efficient feedback there would have to be 10 times more [O~III]-emitting gas than we detected at its position of maximum kinetic luminosity. Three targets show extended [O~III] emission, but compact outflow regions. This may be due to different mass profiles or different evolutionary histories.

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arXiv2020

Gemini Near-Infrared Field Spectrograph Observations of the Seyfert 2 Galaxy Mrk 3: Feeding and Feedback on Galactic and Nuclear Scales

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 $=$ 129\arcdeg, offset from the major axis of the host S0 galaxy at PA $=$ 28\arcdeg, 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$20\arcsec\ ($\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.

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arXiv2020

Mass Outflow of the X-ray Emission Line Gas in NGC 4151

We have analysed Chandra/High Energy Transmission Gratings spectra of the X-ray emission line gas in the Seyfert galaxy NGC 4151. The zeroth order spectral images show extended H- and He-like O and Ne, up to a distance $r \sim$ 200 pc from the nucleus. Using the 1st order spectra, we measure an average line velocity $\sim -230$ km s$^{-1}$, suggesting significant outflow of X-ray gas. We generated Cloudy photoionisation models to fit the 1st order spectra. We required three emission-line components, with column density, log$N_{H}$, and ionisation parameter, log$U$, of 22.5/1.0, 22.5/0.19, and 23.0/-0.50, respectively. To estimate the total mass of ionised gas and the mass outflow rates, we applied the model parameters to fit the zeroth order emission-line profiles of Ne~IX and Ne~X. We determined the total mass of $\approx 5.4 \times$ 10$^{5}$ M_sun. Assuming the same kinematic profile as that for the [O~III] gas, the peak X-ray mass outflow rate was $\approx 1.8$ M_sun yr$^{-1}$, at $r \sim 150$ pc. The total mass and mass outflow rates are similar to those determined using [O~III], implying that the X-ray gas is a major outflow component. However, unlike the optical outflows, the X-ray outflow rate does not drop off at $r >$ 100 pc, which suggests that it may have a greater impact on the host galaxy.

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arXiv2019

Quantifying Feedback from Narrow Line Region Outflows in Nearby Active Galaxies. II. Spatially Resolved Mass Outflow Rates for the QSO2 Markarian 34

We present spatially resolved mass outflow rate measurements ($\dot M_{out}$) for the narrow line region of Markarian 34, the nearest Compton-thick type 2 quasar (QSO2). Spectra obtained with the Hubble Space Telescope and at Apache Point Observatory reveal complex kinematics, with distinct signatures of outflow and rotation within 2 kpc of the nucleus. Using multi-component photoionization models, we find that the outflow contains a total ionized gas mass of $M \approx 1.6 \times 10^6 M_{\odot}$. Combining this with the kinematics yields a peak outflow rate of $\dot M_{out} \approx 2.0 \pm 0.4~M_{\odot}$ yr$^{-1}$ at a distance of 470 pc from the nucleus, with a spatially integrated kinetic energy of $E \approx 1.4 \times 10^{55}$ erg. These outflows are more energetic than those observed in Mrk 573 and NGC 4151, supporting a correlation between luminosity and outflow strength even though they have similar peak outflow rates. The mix of rotational and outflowing components suggests that spatially resolved observations are required to determine accurate outflow parameters in systems with complex kinematics. (See appended erratum for updated values.)

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arXiv2019

Interferometric Fringe Visibility Null as a Function of Spatial Frequency: a Probe of Stellar Atmospheres

We introduce an observational tool based on visibility nulls in optical spectro-interferometry fringe data to probe the structure of stellar atmospheres. In a preliminary demonstration, we use both Navy Precision Optical Interferometer (NPOI) data and stellar atmosphere models to show that this tool can be used, for example, to investigate limb darkening. Using bootstrapping with either multiple linked baselines or multiple wavelengths in optical and infrared spectro-interferometric observations of stars makes it possible to measure the spatial frequency $u_0$ at which the real part of the fringe visibility ${\rm Re}(V)$ vanishes. That spatial frequency is determined by $u_0 = B_\perp/λ_0$, where $B_\perp$ is the projected baseline length, and $λ_0$ is the wavelength at which the null is observed. Since $B_\perp$ changes with the Earth's rotation, $λ_0$ also changes. If $u_0$ is constant with wavelength, $λ_0$ varies in direct proportion to $B_\perp$. Any departure from that proportionality indicates that the brightness distribution across the stellar disk varies with wavelength via variations in limb darkening, in the angular size of the disk, or both. In this paper, we introduce the use of variations of $u_0$ with $λ$ as a means of probing the structure of stellar atmospheres. Using the equivalent uniform disk diameter $θ_{\rm UD, 0}(λ_0)$, given by $θ_{\rm UD, 0} = 1.22/u_0(λ_0)$, as a convenient and intuitive parameterization of $u_0(λ_0)$, we demonstrate this concept by using model atmospheres to calculate the brightness distribution for $ν$ Ophiuchi and predict $θ_{\rm UD, 0}(λ_0)$, and then comparing the predictions to coherently averaged data from observations taken with the NPOI.

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arXiv2018

Quantifying Feedback from Narrow Line Region Outflows in Nearby Active Galaxies. I. Spatially Resolved Mass Outflow Rates for the Seyfert 2 Galaxy Markarian 573

We present the first spatially resolved mass outflow rate measurements ($\dot M_{out}$) of the optical emission line gas in the narrow line region (NLR) of a Seyfert 2 galaxy, Markarian 573. Using long slit spectra and [O III] imaging from the Hubble Space Telescope and Apache Point Observatory in conjunction with emission line diagnostics and Cloudy photoionization models, we find a peak outflow rate of $\dot M_{out} \approx$ 3.4 $\pm$ 0.5 $M_{\odot}$ yr$^{-1}$ at a distance of 210 pc from the central supermassive black hole (SMBH). The outflow extends to distances of 600 pc from the nucleus with a total mass and kinetic energy of $M \approx 2.2 \times 10^6 M_{\odot}$ and $E \approx 5.1 \times 10^{54}$ erg, revealing the outflows to be more energetic than those in the lower luminosity Seyfert 1 galaxy NGC 4151 (Crenshaw et al. 2015). The peak outflow rate is an order of magnitude larger than the mass accretion and nuclear outflow rates, indicating local in-situ acceleration of the circumnuclear NLR gas. We compare these results to global techniques that quantify an average outflow rate across the NLR, and find the latter are subject to larger uncertainties. These results indicate that spatially resolved observations are critical for probing AGN feedback on scales where circumnuclear star formation occurs.

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arXiv2018

An outflow in the Seyfert ESO 362-G18 revealed by Gemini-GMOS/IFU Observations

We present two-dimensional stellar and gaseous kinematics of the inner 0.7 $\times$ 1.2 kpc$^{2}$ of the Seyfert galaxy ESO 362-G18, derived from optical spectra obtained with the GMOS/IFU on the Gemini South telescope at a spatial resolution of $\approx$170 pc and spectral resolution of 36 km s$^{-1}$. ESO 362-G18 is a strongly perturbed galaxy of morphological type Sa or S0/a, with a minor merger approaching along the NE direction. Previous studies have shown that the [OIII] emission shows a fan-shaped extension of $\approx$ 10\arcsec\ to the SE. We detect the [OIII] doublet, [NII] and H$α$ emission lines throughout our field of view. The stellar kinematics is dominated by circular motions in the galaxy plane, with a kinematic position angle of $\approx$137$^{\circ}$. The gas kinematics is also dominated by rotation, with kinematic position angles ranging from 122$^{\circ}$ to 139$^{\circ}$. A double-Gaussian fit to the [OIII]$λ$5007 and H$α$ lines, which have the highest signal to noise ratios of the emission lines, reveal two kinematic components: (1) a component at lower radial velocities which we interpret as gas rotating in the galactic disk; and (2) a component with line of sight velocities 100-250 km s$^{-1}$ higher than the systemic velocity, interpreted as originating in the outflowing gas within the AGN ionization cone. We estimate a mass outflow rate of 7.4 $\times$ 10$^{-2}$ M$_{\odot}$ yr$^{-1}$ in the SE ionization cone (this rate doubles if we assume a biconical configuration), and a mass accretion rate on the supermassive black hole (SMBH) of 2.2 $\times$ 10$^{-2}$ M$_{\odot}$ yr$^{-1}$. The total ionized gas mass within $\sim$84 pc of the nucleus is 3.3 $\times$ 10$^{5}$ M$_{\odot}$; infall velocities of $\sim$34 km s$^{-1}$ in this gas would be required to feed both the outflow and SMBH accretion.

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arXiv2018

Hubble Space Telescope Observations of Extended [O III] λ5007 Emission in Nearby QSO2s: New Constraints On AGN / Host Galaxy Interaction

We present a Hubble Space Telescope (HST) survey of extended [O III] λ5007 emission for a sample of 12 nearby (z < 0.12), luminous Type 2 quasars (QSO2s), which we use to measure the extent and kinematics of their AGN-ionized gas. We find the size of the observed [O III] regions scale with luminosity in comparison to nearby, less luminous Seyfert galaxies and radially outflowing kinematics to exist in all targets. We report an average maximum outflow radius of $\sim$600 pc, with gas continuing to be kinematically influenced by the central AGN out to an average radius of $\sim$1130 pc. These findings question the effectiveness of AGN being capable of clearing material from their host bulge in the nearby universe and suggest that disruption of gas by AGN activity may prevent star formation without requiring evacuation. Additionally, we find a dichotomy in our targets when comparing [O III] radial extent and nuclear FWHM, where QSO2s with compact [O III] morphologies typically possess broader nuclear emission-lines.

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arXiv2018

Outflows in the Narrow Line Region of Bright Seyfert Galaxies - I: GMOS-IFU Data

We present two-dimensional maps of emission-line fluxes and kinematics, as well as of the stellar kinematics of the central few kpc of five bright nearby Seyfert galaxies -- Mrk\,6, Mrk\,79, Mrk\,348, Mrk\,607 and Mrk\,1058 -- obtained from observations with the Gemini Multi-Object Spectrograph (GMOS) Integral Field Unit (IFU) on the Gemini North Telescope. The data cover the inner 3\farcs5$\times$5\farcs0 -- corresponding to physical scales in the range 0.6$\times$0.9 to 1.5$\times$2.2\,kpc$^2$ -- at a spatial resolution ranging from 110 to 280 pc with a spectral coverage of 4300 -- 7100\,Å and velocity resolution of $\approx$ 90\,km\,s$^{-1}$. The gas excitation is Seyfert like everywhere but show excitation, but show excitation gradients that are correlated with the gas kinematics, reddening and/or the gas density. The gas kinematics show in all cases two components: a rotation one similar to that observed in the stellar velocity field, and an outflow component. In the case of Mrk607, the gas is counter-rotating relative to the stars. Enhanced gas velocity dispersion is observed in association to the outflows according to two patterns: at the locations of the highest outflow velocities along the ionization axis or perpendicularly to it in a strip centered at the nucleus that we attribute to an equatorial outflow. Bipolar outflows are observed in Mrk\,348 and Mrk\,79, while in Mrk\,1058 only the blueshifted part is clearly observed, while in the cases of Mrk\,6 and Mrk\,607 the geometry of the outflow needs further constraints from modeling to be presented in a forthcoming study, where the mass flow rate and powers will also be obtained.

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arXiv2017

Disentangling the near infrared continuum spectral components of the inner 500 pc of Mrk 573: two-dimensional maps

We present a near infrared study of the spectral components of the continuum in the inner 500$\times$500 pc$^2$ of the nearby Seyfert galaxy Mrk573 using adaptive optics near-infrared integral field spectroscopy with the instrument NIFS of the Gemini North Telescope at a spatial resolution of $\sim$50 pc. We performed spectral synthesis using the {\sc starlight} code and constructed maps for the contributions of different age components of the stellar population: young ($age\leq100$ Myr), young-intermediate ($100 2$ Gyr) to the near-IR K-band continuum, as well as their contribution to the total stellar mass. We found that the old stellar population is dominant within the inner 250 pc, while the intermediate age components dominate the continuum at larger distances. A young stellar component contributes up to $\sim$20% within the inner $\sim$70 pc, while hot dust emission and featureless continuum components are also necessary to fit the nuclear spectrum, contributing up to 20% of the K-band flux there. The radial distribution of the different age components in the inner kiloparsec of Mrk573 is similar to those obtained by our group for the Seyfert galaxies Mrk1066, Mrk1157 and NGC1068 in previous works using a similar methodology. Young stellar populations ($\leq$100 Myr) are seen in the inner 200-300 pc for all galaxies contributing with $\ge$20% of the K-band flux, while the near-IR continuum is dominated by the contribution of intermediate-age stars ($t=$100 Myr-2 Gyr) at larger distances. Older stellar populations dominate in the inner 250 pc.

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arXiv2014

A Minor Merger Caught In The Act Of Fueling The AGN In Mrk 509

In recent observations by the Hubble Space Telescope (HST) as part of a campaign to discover locations and kinematics of AGN outflows, we found that Mrk 509 contains a 3$''$ ($\sim$2100 {\it pc}) linear filament in its central region. Visible in both optical continuum and [OIII] imaging, this feature resembles a `check mark' of several knots of emission that travel northwest to southeast before jutting towards the nucleus from the southwest. Space Telescope Imaging Spectrograph (STIS/HST) observations along the inner portion of the filament reveal redshifted velocities, indicating that the filament is inflowing. We present further observations of the nucleus in Mrk 509 using the Gemini Near-Infrared Integral Field Spectrograph (NIFS), from which we conclude that this structure cannot be related to previously studied, typical NLR outflows and instead embodies the remains of an ongoing minor merger with a gas-rich dwarf galaxy, therefore providing a great opportunity to study the fueling of an AGN by a minor merger in progress.

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arXiv2014

Feedback from Mass Outflows in Nearby Active Galactic Nuclei. II. Outflows in the Narrow-Line Region of NGC 4151

We present a detailed study of AGN feedback in the narrow-line region (NLR) of the Seyfert 1 galaxy NGC 4151. We illustrate the data and techniques needed to determine the mass outflow rate and kinetic luminosity of the outflowing ionized gas as a function of position in the NLR. We find that the mass outflow rate peaks at a value of 3 solar masses per year at a distance of 70 pc from the central supermassive black hole (SMBH), which is about 10 times the outflow rate coming from inside 13 pc, and 230 times the mass accretion rate inferred from the bolometric luminosity of NGC 4151. Thus, most of the outflow must arise from "in situ" acceleration of ambient gas throughout the NLR. The kinetic luminosity peaks at 90 pc and drops rapidly thereafter, indicating that most of the kinetic energy is deposited within about 100 pc from the SMBH. Both values exceed the mass outflow rate and kinetic luminosity determined for the UV/X-ray absorber outflows in NGC 4151, indicating the importance of NLR outflows in providing feedback on scales where circumnuclear star formation and bulge growth occur.

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