Abstract
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 ∼600 pc, with gas continuing to be kinematically influenced by the central AGN out to an average radius of ∼ 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.
INTRODUCTION
Active galactic nuclei (AGN) are powered by the accretion of matter onto a supermassive black hole (SMBH), which generates massive amounts of radiation within a very small volume. Mass outflows of ionized gas, a spatially-resolved component of AGN feedback, are also generated and have been thought to be critical in the chemical enrichment of the intergalactic medium (Khalatyan et al. 2008) , and the self-regulation of SMBH growth (Hopkins et al. 2005) . The relationship between the SMBH mass and the stellar velocity of its galaxy bulge, i.e. the M BH − σ relation (Kormendy & Ho 2013 and references therein), is credited to ignition of the AGN quenching star formation and evacuating gas from the bulge.
AGN feedback exists in two forms: radio jets and "AGN winds". Jets are powerful and clearly impact their host galaxies and extragalactic environments. However, they are highly focused, and strong jets occur in only 5 -10% of the AGN population (Rafter et al. 2009 ). Alternatively, winds are prevalent in most AGN (Mullaney et al. 2013; Genzel et al. 2014; Woo et al. 2016) , including nearby, moderate luminosity Seyfert galaxies. AGN winds are often observed as UV and X-ray absorption lines blueshifted with respect to their host galaxies, traveling at velocities up to ∼ 2500 km s −1 within tens of parsecs from the central SMBH (Crenshaw et al. 2003; Veilleux et al. 2005; Crenshaw & Kraemer 2012; King & Pounds 2015) , or emission-line gas in AGN narrowline regions (NLRs) on larger scales (100s -1000s of pc), with outflow velocities up to ∼ 2000 km s −1 (Crenshaw & Kraemer 2005; Crenshaw et al. 2010; Müller-Sánchez et al. 2011; Fischer et al. 2013 Fischer et al. , 2014 Nevin et al. 2016) . This is likely to be the region where interaction between AGN and nuclear star formation occurs. One aspect not addressed in this work is molecular gas outflows. Recent studies (Veilleux et al. 2013; Cicone et al. 2014 ) have found evidence for molecular outflows in AGN on large (> 1 kpc) scales; however, most of the AGN in these works are in merged systems, whereas only one source, 2MASX-J0802593+2552551, shows evidence for an ongoing merger in our sample. Therefore, although we cannot rule out the presence of large-scale molecular outflows, the distribution of gas and dynamics in these AGN are likely much different than in merged systems and more consistent with typical low-z Seyfert galaxies (Fischer et al. 2013) .
Recently, we used the Gemini Near-Infrared Integral Field Spectrograph (NIFS) to observe the NLR of the luminous, nearby Seyfert 2 galaxy Mrk 573 (Fischer et al. 2017) . From this work, we found the NLR morphology to be consistent with an intersection between spiral arms in the host disk and ionizing radiation from the central engine, as dust lanes rotating in the host disk (also traced by molecular hydrogen emission) were found to connect to arcs of ionized gas inside the AGN ionizing bicone from outside of the field of ionizing radiation. Host disk gas inside the ionizing field at small radii (r < 750 pc) is radiatively driven away from the central engine and forms the NLR of the AGN, while ionized gas at greater radii follows the rotation kinematics of the host disk as part of the Extended NLR (ENLR; Unger et al. 1987) . Applying these findings to other, similar highresolution kinematics studies of nearby, inclined Seyferts (Das et al. 2005 (Das et al. , 2006 Crenshaw et al. 2010; StorchiBergmann et al. 2010; Müller-Sánchez et al. 2011; Fischer et al. 2013) , where projection effects on outflow distances are small, gas in the radially driven NLRs (i.e. gas with predominantly radial velocity structure) typically extend less than 1 kpc from the central engine. These observations question how successful AGN feedback is on galaxy-bulge scales that may be required in a bulge-quenching, negative feedback scenario. One aspect that may explain these findings is that Seyferts are relatively low-luminosity AGN. Therefore, outflows may not be powerful enough in these nearby AGN to drive gas out to bulge-radius distances.
While one would expect that the power of these outflows would scale with luminosity, as suggested by Ganguly & Brotherton (2008) , ground-based studies of QSO2s (Greene et al. 2011; Liu et al. 2013b; Harrison et al. 2014; McElroy et al. 2015) have found mostly chaotic, low velocity [O III] profiles attributed to AGN activity, with kpc-scale, high-velocity outflows, being exceptionally rare. Studies of SDSS J135646.11+102609.1 (Greene et al. 2011 (Greene et al. , 2012 , for example, find outflows on scales of ∼10 kpc, with deprojected velocities of ∼1000 km s −1 . Additionally, previous analysis of optical longslit observations of the nearby QSO2 Mrk 34 (Fischer et al. 2013) , measured bright, non-rotational kinematics (i.e. outflows) at distances of > 1 kpc. However, the absence of evidence for such outflows in a majority of observations raises the question of whether kpc-scale winds exist in most QSO2s. If they do not, it follows that outflows are not a critical component of quasar-mode feedback and the evolution of galaxy bulges, implying that the star formation is quenched in bulges by other means. As such, we have obtained HST imaging and spectroscopy of 12 of the most luminous QSO2s within z = 0.12, through Hubble Program ID 13728 (PI: Kraemer) and archive observations of Mrk 34, to map [O III] velocities and widths as a function of radial distance and determine the extent of AGN-driven outflows in each system.
SAMPLE, OBSERVATIONS, AND MEASUREMENTS

Target Selection
Our sample is listed in Table 1 and includes 12 of the 15 most luminous targets from the Reyes et al. (2008) QSO2 sample under z = 0.12. Our choice of distance limit was made to ensure our ability to map the structure of the [O III] gas at scales of several 100 pcs for our most distant targets, while opting for the most luminous targets assures that we are studying AGN more luminous than the Seyfert galaxies in our previous kinematic studies. All targets have a log L [O III] ≥ 42.28, satisfying the conventional B-band absolute magnitude criterion of a "quasar", M B < -23, where a corresponding Zakamska et al. 2003) , and are among the top 25% of QSO2s under z = 0.3 in the Reyes et al. (2008) sample. The majority of the sample are radio quiet, with a few being intermediately radio-loud, which indicates, in analogy to nearby Seyferts, that outflows are not likely to be jet driven. Minimum SMBH mass estimates required to produce the observed [O III] radiation range between 10 7.7 -10 8.3 M ⊙ , calculated using the [O III] measurements from Reyes et al. (2008) and assuming an AGN radiating at Eddington with (Heckman et al. 2004) . If these sources are heavily reddened, the bolometric correction and resulting black hole masses would be larger. In order to best sample extended NLR kinematics in each target, Type 2 QSOs were chosen rather than QSO1s, as AGNionized gas morphologies in QSO1s can be strongly foreshortened by projection effects.
HST Observations
Knowledge of the ionized-gas morphology of each AGN was required in order to properly place the STIS longslit across its greatest extension in each AGN. Therefore, the observing program for our sample was performed in a two-step process: obtaining narrow-band images of each AGN to determine ideal STIS position angles and returning at a later date for the follow-up spectroscopic observation. Images were obtained for each QSO2 in our sample using FR505N and FR551N filters, chosen depending on redshift of each target to observe [O III], with the Wide-Field Channel (WFC) of HST / ACS. Continuum observations were obtained using the FR647M filter, selected to provide a relatively broad continuum region free of strong emission lines, for continuum subtraction. Images were obtained between 2014 October 29 and 2015 July 8.
Long-slit spectra were obtained using HST/STIS, with the CCD detector employing the 52 ′′ × 0.2 ′′ slit. Spectra were obtained between 2015 January 29 and 2016 March 3, using either the G430M or G750M medium-dispersion grating, also dependent on the redshift of each target to observe [O III] . Spectral resolutions for the G430M and G750M gratings are 0.56 and 1.1Å (for bandwidths of 286 and 572Å)respectively, with an angular resolution of 0.051 ′′ per pixel in the cross-dispersion direction. Slit position angles for each observation were aligned within 5
• of the projected axis of the ionized-gas observed in the previously obtained HST imaging. Spectra were taken as a combination of three exposures of similar exposure lengths optimized to maximize available observing time in a single orbit. Observations were dithered by ±0.25 ′′ along the slit with respect to the first spectrum to avoid problems due to hot pixels, and wavelength calibration lamp spectra were taken during Earth occultation.
Our sample also includes archival imaging and spectroscopic observations (Proposal IDs: 10873 and 8253, respectively) 
Data Reduction
Data reduction for continuum and on-band images followed the standard HST pipeline procedures. On-band and continuum images were observed sequentially, not requiring realignment between images. The flux calibration of the FR647M and F467M continuum images and the FR505N, FR551N, and F547M on-band images was done in the standard way, using the information available on the image headers. Photometrically calibrated, 2D-rectified images of each long-slit observation were processed using Interactive Data Language software where multiple, dithered observations of each target were aligned and combined into a single, averaged dataset. The final [O III] images of the galaxies are presented in Figures 3 -9 . The lowest contour value of these images corresponds to the 3σ level above the background in surface brightness, with interior contours increasing in powers of 2 × 3σ.
[O III] Spectroscopic Fitting
[O III] λ5007 kinematics and fluxes in our STIS observations were measured by fitting the emission line in each row of the 2D STIS CCD spectral image with Gaussians in an automated routine (Figure 2 ). Our fitting process, previously discussed in depth in Fischer et al. (2017) uses the Importance Nested Sampling algorithm as implemented in the MultiNest library (Feroz & Hobson 2008; Feroz et al. 2009 Feroz et al. , 2013 Buchner et al. 2014) to compute the logarithm of the evidence, lnZ, for models containing a continuum plus zero, one, two, and three Gaussian components per emission line. When comparing two models, i.e. a model with zero Gaussians (M 0 ) and a model with one Gaussian (M 1 ), the simpler model is chosen unless the more complex model, M 1 , has a significantly better evidence value, |ln(Z 1 /Z 0 )| > 5 (99% more likely Initial input parameters in our models are selected based on physical considerations. The centroid position for each Gaussian was limited to a 40Å range around the systemic [O III] wavelength that contained the entirety of the line profile throughout each long-slit data set. Gaussian standard deviation ranged from the spectral resolution of the G430M / G750M gratings, to an artificial limit of 15Å ([O III] FWHM ∼2000 km s −1 ). Gaussian height was permitted to range from a minimum height of 3 times the standard deviation of the adjacent continuum (3σ) to a virtually unbound maximum height restriction of 3σ× 10 8 .
2.5. Host Disk Elliptical Fitting As illustrated in Fischer et al. (2017) , spatiallyresolved, AGN-ionized gas can be explained as illuminated material located near the plane of the host disk, where rotating molecular gas outside the AGN area of influence in Mrk 573 connects to the ionized-gas structures inside the AGN area of influence. Therefore, if we assume that a majority of AGN ionized-gas structure in other Type 2 AGN also resides in their host disks, we can employ information on the host disk orientation of each target to deproject HST measurements for our QSO2 sample and determine true physical distances. Continuum imaging of our sample was obtained in our HST dataset, however these observations were intended for continuum subtraction of [O III] imaging and are too shallow for independent orientation analysis. Measurements of host disk ellipticities (e) and major axis position angles (PA MA ) were therefore obtained by fitting ellipses to isophotes in gri Sloan Digital Sky Survey (SDSS; York et al. 2000; Eisenstein et al. 2011 ) imaging of each galaxy using the ellipse routine in the STSDAS package of IRAF. Ellipses were fit from the inner ∼ 0.2 ′′ of each image, out to where flux levels reached a 3σ level above the background in all bands. The background level and its standard deviation were determined from blank regions within the SDSS CCD field of each galaxy. Targets with interacting morphologies, 2MASX J08025293+2552551, B2 1435+30, and Mrk 477, were fit to a 5σ level and FIRST J120041.4+314745, which is immediately adjacent to a neighboring galaxy, was fit to a 9σ level to avoid fit disturbances in low flux isophotes. Ellipse parameters obtained from the fit of each SDSS image are shown in Appendix Figures 13 -18 . Final values of PA MA and e used for our calculations, as listed in Table 2 , are the average of values taken from each band at the greatest distance where the minimum S/N measurements exist in all bands. The difference in host major axis and STIS observation position angles is also provided in Table 2 as PA dif f .
RESULTS

Morphologies
Continuum-subtracted [O III] images were used to measure the projected extension of AGN ionization in these galaxies. Using the continuum centroid as the nucleus location in each galaxy, we measured the length Reyes et al. (2008) . Column 7 lists the minimum SMBH mass required to produce the observed radiation, assuming an AGN radiating at Eddington with (Heckman et al. 2004) . Column 8 lists radio fluxes from Reyes et al. (2008) . Columns 9 and 10 list the filter/grating and exposure time of each data set. Column 11 lists central wavelengths for each observation. Column 12 lists spectroscopic long-slit position angles. was not extended enough to accurately determine a PA. Table 3 gives the measured values of R max , R 90% , PA, and the 3σ flux density used to trace the extent of the [O III] gas, with angular radii converted to true radii using scales listed in Table 1 derived from the luminosity distance of each target.
3.2. Kinematics We mapped the observed ionized-gas kinematics in each galaxy by extracting Gaussian parameters from the best fit to the [O III] λλ4959,5007 emission-line for each row of the 2D spectral images of our long-slit data, as seen in Figure 1 . Resultant velocities (given in the rest frame of the galaxy and using a vacuum rest wavelength of 5008.24Å.), FWHMs, and integrated fluxes (integrated under the Gaussian) for individual Gaussian components along each QSO2 long-slit spectrum in our sample are shown in the right side of Figures 3 -6 , with left to right progression representing 0.05" steps along the STIS longslit and a 0.0" offset located over the continuum centroid observed in imaging. Spectra containing multiple Gaussian components, as seen in Figure 2 , are sorted by measured FWHM, with blue circles, green diamonds, and red squares corresponding to first-, second-, and third-widest FWHM components respectively. Specifically, Gaussian parameters extracted from the emission-line fits in Figure  2 are seen reproduced at the 0.0" offset in the kinematics plots of 2MASX J08025293+2552551 in Figure 3 .
Kinematic analysis of the [O III] gas was performed based on our findings from Fischer et al. (2017) , where we found the influence of the central AGN to be stratified into two regions extending from the nucleus. At small radii, outflows are visible as emission-lines deviating from the overall rotation pattern of the system or emissionlines that possess multiple components that travel at different velocities from one another in the NLR. At greater radii, gas is ionized by AGN radiation, but possess velocities and FWHMs consistent with gas in rotation with the host galaxy, as derived by stellar kinematics, in the extended NLR (ENLR). Applying these qualifications to the kinematics of our current sample, we can measure the extent of the outflowing gas within the observed [OIII] emission of each target. In doing so, we also find that several targets exhibit a third, composite set of AGN kinematics where the gas appears to be in rotation but is experiencing some influence by the AGN as FWHM measurements are found to be consistently > 250 km s −1 , indicative of some kinematic disturbance (Bellocchi et al. 2013; Ramos Almeida et al. 2017) . While the gas sampled in these regions is not outflowing, it is being disturbed by the AGN, therefore we reference these regions as 'disturbed' kinematics. We specifically classify the stratification of outflow, disturbed, and non-disturbed rotation kinematics below, from which we measure the extent of outflowing and AGN disturbed gas in each system.
1) AGN driven outflows: Emission-lines exhibit high centroid velocities (> 300 km s −1 ) from systemic and/or emission-lines with multiple components. Velocities do not follow velocity pattern of adjacent regions. The maximum radial extent of these kinematics is measured as R out , designated by dashed lines in both the STIS measurements and the ACS or WFPC2 imaging of Figures 3 [O III] flux contours start at 3σ over background and increase in powers of 2 times 3σ (i.e. 3σ × 2 n ). The position of the nucleus, measured at the continuum-image flux peak of each target, is plotted as a white cross. Dashed, dotteddashed, and solid circles represent Rout, R dist (when different than Rout), and Rmax radii, respectively. Slits depict the position of STIS long-slit positions. Inset images display 20 ′′ × 20 ′′ and 40 ′′ × 40 ′′ r-band SDSS images of 2MASX J07594101+505245 and 2MASX J08025293+2552551, respectively, with the host disk elliptical fit used in our analysis overplotted. North is up and east is left in all images. Right: Velocities, FWHMs, and integrated fluxes (ergs s −1 cm −2 ) for each emission-line component of our kinematic fits to the [O III] λ5007 emission-line along our HST/STIS medium-resolution observations. Kinematic data points are marked as blue circles, green diamonds, and red squares corresponding to components with first-, second-, and third-widest FWHM measurements, respectively. The horizontal, dashed line in FWHM plots signifies the approximate limit for non-disturbed kinematics of 250 km s −1 . Vertical dashed and dotted-dashed lines represent the maximum radius of observed outflows (Rout) and disturbed kinematics (R dist ; when different than Rout), respectively. R dist radii for 2MASX J07594101+505245 are equal in size to Rout. Rout and R dist radii in each target are mirrored across the nucleus to illustrate the maximum extent of each region and associate the kinematics to what is observed in imaging, even if no data points exist out to those radii on a given side of the nucleus. Column 2 lists the maximum projected distance of outflowing kinematics. Column 3 lists the maximum projected distance of disturbed kinematics, gas exhibiting FWHM > 250 km/s that is at systemic or follows rotation. Column 4 lists the maximum velocity measured inside Rout, as the maximum outflow velocity. Column 9 lists the ratio of maximum outflow radius to maximum [O III] extent in each target. -9.
2) Disturbed rotation: Single component emissionlines with FWHMs > 250 km s −1 that exhibit low centroid velocities (< 300 km s −1 ) that follow the orderly rotation pattern observed in similar radial distances. The maximum radial extent of these kinematics is measured as R dist , mark with dotted-dashed lines in Figures 3 -9. Targets without R dist dotted-dashed lines have equal R out and R dist measurements.
3) Non-disturbed rotation: Emission lines that exhibit low centroid velocities (< 300 km s −1 ) with low FWHM ( 250 km s −1 ). Consistent with rotation, where measurable non-systemic extents exhibit blueshifts on one side of nucleus, redshifts on other side.
Maximum projected R out and R dist distances in each target are marked in the kinematics plots of Figures 3 -6 and mirrored across the nucleus to illustrate the extent of each region and aid in associating the kinematics to what is observed in imaging, even if no spectroscopic data points exist out to those radii on a given side of the nucleus. Descriptions of the individual R out and R dist measurements for each target are provided in Appendix A, with resultant distances listed in Table 4 .
We deproject our maximum distance measurements of the outflowing and disturbed gas by dividing our maximum projected distances by a scaling factor (s) calculated from the orientation of the [O III] morphology and the orientation and ellipticity of the host galaxy, as determined from our elliptical fits to the SDSS host images: • . After deprojecting our initial measurements, we find that the maximum outflow radii range from 150 to 1890 pc, with a mean value of ∼625 pc, and the observed maximum disturbed radii similarly range from 160 to 1890 pc, with a mean value of ∼ 1130 pc. We note that measurements of disturbed gas radii extend to the full length of our observations in several targets. arcsecond −1 ) for non-merging Seyfert galaxies (Schmitt et al. 2003b ) and higher redshift QSO2s (Liu et al. 2013a) we find a continuous trend between [O III] extent and [O III] luminosity, as shown in Figure 10 . The trend suggests higher luminosity targets produce [O III] out to greater distances. This figure contains three linear fits. The first fit (dashed line), obtained using all observed galaxies has the expression logR max = −18.41 + 0.52logL [OIII] with a Spearman rank of ρ = 0.92 and a slope uncertainty of 0.024. The second fit (solid line) was obtained only using galaxies observed with HST, our targets and those from Schmitt et al. (2003a) , and has the expression logR max = −14.85 + 0.43logL [OIII] with a Spearman rank ρ = 0.82 and a slope uncertainty of 0.031. The third fit (dotted line) was obtained using only HST observed Seyfert 2s and QSO2s. The resulting expression is logR max = −14.45 + 0.42logL [OIII] with a Spearman rank ρ = 0.88 and a slope uncertainty of 0.031.
We find that fits from HST observed targets have similar slopes ∼0.42, with the slight offset from including Seyfert 1s likely due to projection effects. The measured slopes are steeper than the value of 0.33 found by Schmitt et al. (2003b) , but shallower than the value of 0.52 observed by Bennert et al. (2002) . A slope of 0.5, similar to what is found fitting all targets, is consistent with a 1/r dilution of the ionizing radiation, assuming similar gas densities and covering factors in the ENLRs. A smaller value for the slope may simply be due to the absence of gas at large radial distances.
Extent of non-rotating kinematics
In measuring the extent of non-rotating kinematics in our QSO2 sample, we find that the [O III] kinematics observed in Mrk 34 remain exceptionally large, such that the extent of the outflowing gas in this object, R out = 1.89 kpc, is ∼75% larger than the next largest outflow radius in our sample, FIRST J120041.4 at R out = 1.07 kpc, and on average, the observed [O III] gas contains radial outflows extending to a distance of ∼0.6 kpc. As Type 2 AGN have been shown to have systemically lower Eddington ratios than Type 1 AGN (Ricci et al. 2017) , one explanation for the lack of strong, kpc-scale winds in a majority of our sample may be due to low accretion rates. However, our sample contains the most luminous Type 2 AGN from Reyes et al. 2008 within a redshift of z < 0.12, with [OIII] luminosities 3 to 10 times larger than that of Mrk 573. Therefore, it is likely that a majority of our sample is radiating at or near the Eddington limit.
We were not able to determine the bulge radii for the galaxies in our sample to compare to the measured outflow radii as our HST continuum images were too shallow to detect the extent of the bulge and the SDSS images are of such scales that the bulges could not be resolved. However, considering that in the case of Mrk 573 the bulge has an effective radius of ∼1 kpc and that most of its mass is enclosed in a ∼2 kpc radius, even if one makes the simplifying assumption that the QSO2s were located in a similar host galaxy, their winds would most likely not be capable of clearing material from the bulge. Similar to our previous findings in Mrk 573, the [O III] outflow radii in our sample are typically a small fraction of the radii encompassing the entire [O III] structures in their host disks. We note that when comparing the radial extent of [O III] emission between imaging and spectroscopy for these QSO2s, spectroscopic measurements only sample the brightest knots of emission observed in imaging for a majority of our targets. However, it is likely that we are observing the majority of radially outflowing kinematics in all of our targets, as outflows are often observed as the brightest knots of AGN-ionized gas and we observe the kinematics returning from very high velocities or FWHMs by the furthest radial extents of our observations.
As we do not have information on the kinematics of the stellar disks or surrounding molecular hydrogen for these targets to confirm the influence of rotation in our sample, distance measurements reported here are made using the assumption that the observed, extended [O III] emission is created via an intersection between ionizing radiation from the central engine and preexisting, rotating gas in the host disk. Qualitatively, evidence that the extended, low velocity gas in these systems is in rotation exists in the morphologies of the [O III] regions, as the arc structures observed in several systems resemble spiral arms one would expect to reside in their hosts. Quantitatively, if we compare the difference in position angle between the host major axis and the STIS long-slit observation (PA dif f ; Table 2), we find that targets with apparent high amplitude, pronounced rotation curves (i.e. SDSS J115245.66+101623.8 and 2MASX J17135038+5729546) have a smaller PA dif f , while targets with higher PA dif f (i.e. 2MASX J08025293+2552551 and 2MASX J11001238+0846157) exhibit extended velocities near systemic, suggesting we are sampling rotation in the host disk along the major and minor axes, respectively.
Our findings also agree with similar, recent kinematic studies in nearby, non-merging QSOs (Liu et al. 2013b; Harrison et al. 2014; McElroy et al. 2015; Karouzos et al. 2016; Villar-Martín et al. 2016; Keel et al. 2017; Ramos Almeida et al. 2017) , where maximum outflow distances are measured to be between 1 -2 kpc, and disrupted gas kinematics are observed out to several kpcs in a majority of targets. These findings suggest that AGN may still be disrupting gas that would form stars in their host galaxies on bulge-size scales without requiring complete evacuation via outflows.
[OIII] extent vs [OIII] FWHM
The combination of the [O III] images and spectra for the QSO2s in our sample suggest that they can generally be divided into two, distinct categories, as shown in Figure 11 . Specifically, targets with compact [O III] morphologies tend to exhibit broad nuclear FWHMs (>1500 km s −1 ), while targets with more extended [O III] morphologies have narrower nuclear FWHMs (< 900 km s −1 ). 2MASX J14054117+4026326 overlaps with both catagories, as it has a compact [O III] morphology, but also possesses a comparitively small nuclear FWHM of 720 km s −1 . We note that in targets with compact morphologies (2MASX J07594101+505245, 2MASX J11001238+0846157, 2MASX J14054117+4026326, 2MASX J17135038+572954, and Mrk 477), the [O III] extent is so compact that we observe the diffraction spikes typical of a point source in the emission line images. If this is due to an orientation effect, the compact QSO2s would be viewed roughly face-on, similar to Type 1 AGN. However, SDSS spectra of these sources show no evidence of hydrogen emission-lines being broader than [O III] and the continuum images of these targets (Appendix Figures 13 -18) show only the diffuse emission due to the host galaxy and do not show a corresponding nuclear point source that would be expected if these targets were seen face-on. Additionally, other than the broad, central components, the [O III] velocity profiles of the compact sources are generally similar to the extended sources, e.g., 2MASX-J07594101 (Figure 3 ) compared to FIRST-J12004141 (Figure 4) . Therefore, as the compact sources are true Type 2 AGN, the simplest explanation for the broad [O III] FWHMs is the presence of more material closer to the AGN, with large velocity gradients along our line of sight being produced by high velocity gas that is outflowing more isotropically. The presence of high velocity [O III] gas close to the AGN does not necessarily account for the compactness of these sources, as a smaller [O III] morphology in the compact sources could be due to a weaker AGN. However, assuming that [O III] is an isotropic quantity (Heckman et al. 2004) , the five compact sources have roughly the same bolometric luminosities as the remaining sources.
The morphological dichotomy that we observe in our QSO2 sample is analogous to what is seen in nearby, high accretion-rate Seyfert galaxies. For example, Figure 12 shows HST imaging of [O III] morphologies in the Seyfert 2 galaxies NGC 1068 and Mrk 573 at their observed redshifts, which represent galaxies with broad and narrow [O III] FWHMs, respectively. This figure also shows simulated imaging of what we would expect to observe for the same targets at a redshift of z = 0.07, typical of our QSO2 sample. These images were created by resampling the [OIII] images of NGC 1068 and Mrk 573 to the expected resolution at z = 0.07, and convolving these images with the point spread function of a corresponding narrow band filter, to simulate the passage of the image through the telescope optics. The results from this experiment show that in the case of NGC 1068, its [O III] structure is compact enough that if it was placed at a redshift typical of our QSO2s, the [O III] emission would be detected as a point source with fainter line emission surrounding it, similar to what we observe in our compact, high-FWHM targets. Alternatively, in the case of Mrk 573, the resampling and convolution of the image does not cause a significant change to the structure of the [O III] morphology, other than reduced resolution. This is similar to the case of SDSS J115245, a QSO2 with narrow nuclear [O III] FWHM measurements.
A possible explanation for the difference in morphology is that there is more gas close to the AGN in the compact targets, which results in the attenuation of a fraction of ionizing radiation. STIS observations of NGC 1068 support this idea, as they reveal bright, nuclear [O III] emission with FWHM > 1000 km s −1 Das et al. 2006) . Photoionization analysis of these observations, performed by , suggested that the observed ionizing radiation is attenuated by gas close to the AGN. Additionally, the scattered optical continuum is centrally-peaked and, based on Chandra/ACIS imaging, the X-ray source is 165 pc in extent (Young et al. 2001) . Therefore, all of this together indicates there is a large concentration of ionized gas at small radii (100 -200 pc).
It is unlikely that the optical emission-line gas is attenuating much of the ionizing radiation, since, based on our studies of Seyfert galaxies Collins et al. 2009 ), the [O III] gas has a small covering factor. On the other hand, X-ray emission-line gas in the NLR can possess covering factors ∼ unity (e.g., Kraemer et al. 2015) . As the medium responsible for the scattering/polarization of the hidden broad-line emission lines and continuum in Type 2 AGN must possess large covering factors and column densities (Antonucci 1993) , it is possible that the ionizing radiation has been attenuated by absorption/scattering in high ionization gas. Note, however, that there would be strong soft X-ray emission lines formed in the attenuating medium, assuming that elements such as O, N, C and Ne are not fully ionized.
Given the evidence for strong outflows in NGC 1068 (Das et al. 2005 ) and that it is likely radiating near Eddington (Kraemer et al. 2015) , this gas could eventually be driven away from the inner nucleus. This would reduce the amount of emission-line gas at small radial distances, which would weaken or eliminate the broad [O III] . This also could drive out the X-ray emission-line gas, which would reduce the attenuation of the ionizing radiation, resulting in a more extended [O III] structure. As such, it may be that the compact QSO2s are in a similar state, and that a transition occurs from compact AGN, with higher central concentrations of gas, to the more extended sources observed in the remainder of our sample, which resemble Mrk 573 with extended morphologies and nuclear FWHMs ∼ 100s km s −1 (Fischer et al. , 2017 .
CONCLUSIONS
We have analyzed the [O III] morphology and emissionline kinematics of a sample of 12 QSO2s via highresolution imaging and spectroscopy with HST. Our major findings are as follows: 1) Our targets consist of several of the most luminous Type 2 AGN within a redshift of z = 0.12, yet [O III] morphologies in our sample vary from compact, corelike structures to extended structures, all several kpc in length. Overall, the size of [O III] regions scale with luminosity in comparison to non-merging Seyfert galaxies and QSO2s observed to similar sensitivities.
2) Radially outflowing kinematics exist in all of our targets, with maximum outflow distances ranging between 150 and 1890 pc and a mean R out of ∼600 pc. The extent of these outflows are relatively small compared to the overall extent of the [O III] morphology, with an average R out /R max = 0.22. As such, our findings suggest that a majority of observed extended [O III] emission is often in rotation and not driven radially by AGN winds, questioning the effectiveness of AGN being capable of clearing material from their host bulge in the nearby universe.
3) A majority of our sample also show signatures of gas at systemic velocity or following rotation that is disturbed by the central AGN (FWHM > 250 km s −1 ) at distances outside the maximum measured radial outflow radii, with maximum radii ranging from 160 to 1860 pc, with a mean R dist of ∼ 1130 pc. These findings suggest that AGN activity may be disrupting gas that forms stars without requiring complete evacuation. 4) We find our targets fall into two classes when comparing [O III] radial extent and nuclear FWHM, such that QSO2s with a more compact [O III] morphology have broader nuclear emission-lines. We hypothesize that this could be due to a transitional effect, where QSO2s with compact morphologies possess comparatively large amounts of gas near the AGN, which may be driven out at later states. This research has made use of the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration.
Funding for the Sloan Digital Sky Survey IV has been provided by the Alfred P. Sloan Foundation, the U.S. Department of Energy Office of Science, and the Participating Institutions. SDSS-IV acknowledges support and resources from the Center for High-Performance Computing at the University of Utah. The authors thank the anonymous referee for their helpful comments that improved the clarity of this work. T.C. Flux contours start at 3σ over background and increase in powers of 2 times 3σ (i.e. 3σ × 2 n ). The position of the nucleus, measured at the flux peak of each target, is plotted as a white cross. The inset image displays a zoomed-out continuum r-band SDSS image of the target host galaxy with the outer-most elliptical fit overplotted. Right: Position angle and ellipticity outputs of elliptical fits to SDSS g−(green), r−(red), and i−band (blue) imaging out to a 3σ detection for 2MASX J07594101+505245 and 5σ for 2MASX J08025293+2552551.
APPENDIX

INDIVIDUAL TARGET DESCRIPTIONS

2MASX J075941
The [O III] structure in this target is highly asymmetric, with faint, extended knots of emission to the east of the nucleus. Kinematics are obtained near the nucleus (total extent <1"), with a two-component emission line (FWHMs of ∼1500 and 100 km s −1 ) observed near systemic throughout, and an intermediate width component (FWHM ∼ 500 km s −1 ) traveling in different directions on either side of the nucleus inside 500 pc. We measure the maximum extent of these kinematics as the observed outflow radius R out = 620 pc. At greater distances, we measure single component emission-lines at systemic with FWHMs < 250 km s −1 , which we define as undisturbed rotation. As such, we do not measure a distinct disturbed kinematics maximum radius, R dist in this target. This QSO resides in a relatively face-on system, that does not have any companions or tidal tails, suggesting no recent galaxy interaction activity.
2MASX J080252
This QSO has an asymmetric, conical [O III] morphology pointing north of the nucleus. Kinematics are obtained from the nucleus to distances > 1 kpc north, with emission-line fluxes rapidly becoming fainter south of the nucleus, consistent with the opposite cone being extinguished by the host disk. Rapid differences in FWHM and velocity between nucleus and immediately off-nucleus measurements are due to blending of the blueshifted, offset component, as seen in Figure 2 , at off-nuclear positions. R out is measured as the extent of the multicomponent emission lines, which extend along the STIS slit to the northeast approximately 500 pc. Single-component, broad FWHM (>250 km s −1 ) emission-lines near systemic are observed to extend to an additional 200 pc, for an R dist of ∼700 pc. Emissionlines at greater radii to the northeast have a single, narrow (< 250 km s −1 ) component that suggests that the gas is kinematically undisrupted. This target resides in a host that has recently experienced some galaxy interaction, with a long tidal tail extending 15" east of the system. Elliptical fits to this system result in a highly inclined disk, which may be affected by the resultant morphology.
Mrk 34
The [O III] morphology in Mrk 34 is a clear, biconical structure, with a 'Z' shape likely due to the illumination of spiral arms in the host disk, similar to previously observed targets like Mrk 3 and Mrk 573 (Fischer et al. , 2017 . [O III] kinematics across the three separate slit positions show high-velocity (∼1000 km s −1 ) outflows existing inside projected distances of 500 pc. Extended kinematics for the rest of the system appear to be largely rotational, however large deviations from rotation and emission-line splitting are present on either end of the nucleus out to ∼ 1.5 kpc. Here, we observe line splitting with both lines deviating from the rotation curve in opposite directions, to an approximate maximum difference of 500 km s −1 . Regions that display line splitting are observed as the outer arcs being illuminated in the NLR, suggesting that these kinematics are due to material in the spiral arms being driven or ablated in directions perpendicular to the radial outflows. We define R out to encompass the entirety of the observed kinematics with multiple components for a radial distance of 1.50 kpc. This distance also marks the extent of R dist , as kinematics at greater radii follow a likely rotation pattern and have FWHM measurements of approximately 250 km s −1 . The host galaxy of Mrk 34 is a well-resolved spiral galaxy that is moderately inclined with no evidence of merger activity.
Mrk 34 has been studied significantly more than a majority of our targets. VLA radio observations (Falcke et al. 1998 ) show a radio jet structure well-aligned with the optical ionized-gas morphology, where radio hot spots coincide with regions of low excitation. NuSTAR 3-40 keV observations by Gandhi et al. (2014) found that Mrk 34 is the nearest non-merging Compton-thick QSO2, with soft X-ray emission being driven by AGN photoionization versus star formation. This follows the findings that Mrk 34 lacks nuclear star formation (González Delgado et al. 2001; Stoklasová et al. 2009 ), which may be suppressed due to AGN feedback (Wang et al. 2007 ).
2MASX J110012
This target has a compact [O III] morphology, which is nearly circular with diffraction spikes and a slight extension to the southeast. High FWHM emission (> 1000 km s −1 ) is measured across nucleus that is blueshifted to the southeast. We measure R out to the maximum extent of these high FWHM measurements at 450 pc northwest of the nucleus. Disturbed kinematics extend to the furthest observations northwest of the nucleus, R dist = 1 kpc, where we measure single-component emission-lines at systemic with widths of ∼ 500 km s −1 , which may be a product of blending multiple components as observed over the nucleus. This QSO2 resides in a well-resolved barred spiral galaxy that is moderately inclined with no evidence of recent interactions or ongoing mergers.
SDSS J115245
This target has a clear biconical [O III] morphology, with arcs of emission that suggest that a majority of the gas exists in illuminated spiral arms. The observed kinematics appear to be largely rotational, with redshifted rotation to the north and blueshifted rotation to the south. High peak rotation velocities (∼200 km s −1 ) are consistent with the alignment between the modeled host major axis and STIS long-slit position angles (PA dif f = 33.3
• ). Narrow emission line components are measured going in the opposite direction of rotation immediately northeast of the nucleus, which represent the extent of outflows with R out = 130 pc. ∼ 400 km s −1 FWHM gas is observed in rotation at radii outside the first northern arc of emission, for an R dist of ∼1.1 kpc. The host galaxy for this target is moderately inclined with no signs of recent interaction activity.
FIRST J120041
FIRST J120041 has the largest projected [O III] morphology extent in our sample, with an R max of ∼6 kpc, which is on the same scale as the extent of the observable host galaxy in SDSS imaging. [O III] velocities are measured on much smaller scales, extending to distances between 0.8 -1.5 kpc from the nucleus, which can be mapped to the two bright lobes on either side of the nucleus along the STIS slit. Multi-component and high-velocity emission lines are observed in the inner 0.5", for an R out of ∼1 kpc, with high FWHM, single-component emission lines detected to the furthest extent of our measurements (R dist = 1.12 kpc). Outflows and disturbed kinematics may reach to further distances outside the area sampled by the STIS slit, as the bright knots where we observe the high-velocity gas extend to a radius of ∼0.76 ′′ , or ∼1.55 kpc. This target appears to be part of an ongoing or recent interaction with a smaller, satellite galaxy to the southwest, as filamentary structure can be observed linking the two systems.
2MASX J130038
The [O III] structure of this target is extended, with two arcs of bright emission and a linear feature near the nucleus, suggesting that the observed morphology is due to spiral arms being illuminated by the central engine. The kinematics sampled by our STIS observations agree with this interpretation, as they appear to be largely in kinematically undisturbed rotation. Velocities are blueshifted to the southeast and redshifted to the northwest, with FWHMs ranging between 100 -200 km s −1 . A compact, broad FWHM component is observed immediately northwest of the nucleus, with R out ∼160 pc, suggesting outflows are being driven off the linear filament near the nucleus observed in imaging, similar to Mrk 573. As single-component emission lines at greater radii possess FWHMs < 250 km s −1 , R out and R dist are the same distance. The host of this QSO2 appears to be relatively face-on without any signs of recent interactions. 
2MASX J140541
This source has a compact [O III] morphology. The measured R max is inside the observed [O III] morphology as it is artificially extended by diffraction spikes. Kinematics show the gas to be near systemic, with slightly blueshifted outflows over the nucleus possessing FWHMs of ∼800 km s −1 out to an R out ∼ 300 pc. FWHM measurements remain near 400 km s −1 for single-component emission lines at the furthest extent of our measurements, suggesting kinematically disturbed gas exist throughout (R dist ∼ 850 pc). The farther extension of gas kinematics to the northwest suggest that the host disk may be extinguishing emission to the southeast. The host is moderately inclined, without signs of recent interaction activity.
B2 1435+30
The [O III] morphology of B2 1435+30 is biconical, with a compact arc to the east, and a bright, extended cone to the west, which are both traced kinematically by our STIS observations. This target does not possess significantly high velocities or multiple components in its kinematics, however, we find that the redshifted, high FWHM (∼700 km s −1 ) gas kinematics over the nucleus do not follow the overall rotation pattern of the surrounding gas at greater radii and deem these kinematics to be in outflow, with R out = 170 pc. Kinematics across the features outside the nucleus resemble kinematically disturbed rotation, observed as 400 km s −1 FWHM gas, extending throughout the southwest cone, with R dist > 1.5 kpc. This target appears to be part of a recent galaxy interaction, with extended structure in SDSS imaging linking it to an eastern satellite galaxy.
Mrk 477
The [O III] morphology of this target is largely comprised of two emission line knots inside 500 pc, with fainter emission extending to radii of ∼2.5 kpc. [O III] kinematics suggest that the gas is largely in rotation near systemic, with additional emission over the nucleus extending to radii ∼500 pc that displays multiple emission-line components and excessively large FWHMs ∼ 2000 km/s. Relatively moderate FWHM (> 500 km s −1 ), single-component, nearsystemic emission-line kinematics extend to further distances of R dist = 840 pc. This target resides in a well-resolved spiral galaxy that shows signs of a recent interaction in tidal streams that bridge Mrk 477 to neighboring galaxies to the northeast (De Robertis 1987) .
Similar to Mrk 34, Mrk 477 is also well-studied. UV through near-IR analysis by Heckman et al. (1997) show that a large portion of the energetics in this system is provided by an ongoing compact, nuclear starburst in this target. 8.4 GHz radio emission extends to a radius of ∼500 pc along a position angle ∼ 30
• , similar to our STIS long-slit position. 
2MASX J165315
The [O III] morphology in this target is distributed in three features; a faint arc ∼ 4 kpc east of the nucleus, a central lobe extending east from the nucleus, and a fan or conical shape west of the nucleus. [O III] kinematics are only obtained for the central lobe and western fan, with a largely rotational pattern. The maximum outflow radius is defined by a relatively broad (>500 km s −1 ), systemic, (or blueshifted with respect to the narrow component), secondary component observed east of the nucleus for an R out = 370 pc. Single-component line emission with FWHM > 250 km s −1 that follows a low amplitude rotation pattern is measured throughout the rest of the system, for an R dist of 1.1 kpc. The host galaxy of this target is moderately inclined, with no signs of a recent merger.
2MASX J171350
Similar to 2MASX J140541, this source has a compact [O III] morphology and the measured R max is inside the observed [O III] morphology as it is artificially extended by diffraction spikes. Kinematics in this system follow a rotation pattern, redshifted to the northeast and blueshifted to the southwest, with broad emission-line FWHMs frequently around 1500 km s −1 . High peak rotation velocities (∼200 km s −1 ) are consistent with the alignment between the modeled host major axis and STIS long-slit position angles (PA dif f = 16.3
• ). Multi-component emission lines are Figure 18 . Same as Figure 13 for 2MASX J16531506+2349431 and 2MASX J17135038+5729546. Host disk ellipticals are fit to 3σ for both targets.
observed out to 490 pc, which we define as R out . Blending of these components likely occurs in measurements near the ends of our STIS observations, with the very broad component becoming too faint to individually detect at a 3σ level, creating a single-component emission line possessing disturbed kinematics that extends to an R dist of ∼700 pc. The host is moderately inclined, without signs of a recent merger.

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