arXiv subjects

Nahum Arav

Publications and source records attributed to Nahum Arav.

At least 19 recordsLinked to original sources

arXiv2026

Mapping a Quasar Outflow from Parsec to Kiloparsec Scales: A Combined HST Absorption and VLT Emission Investigation

Linking nuclear winds to galactic-scale outflows remains a major observational challenge in understanding the multiscale physics of active galactic nuclei feedback. Here we present VLT/KMOS integral-field spectroscopy and SDSS observations of the $z = 0.9655$ quasar PKS J0352$-$0711. Our analysis reveals complex, multi-ionization emission, including a fast, unresolved nuclear wind and a spatially resolved galactic-scale outflow. We integrate the [O III] emission properties with those deduced from the mini-broad-absorption-line outflows detected in HST/COS observations of this quasar. This unique combination of datasets allows us to trace, for the first time, the physical progression of a quasar outflow from $\sim$ 10 pc to 10 kpc. The multiscale kinematics support a unified evolutionary scenario where the inner, constant-velocity ($\sim-3800 \textrm{ km s}^{-1}$) expansion of the wind is traced jointly in absorption ($\sim 9$ pc) and emission ($\gtrsim 40$ pc). As the wind propagates to $\sim$ 500 pc, the intermediate absorption system reveals a deceleration to $\sim-2100 \textrm{ km s}^{-1}$, consistent with mass-loading from the interstellar medium. Finally, our spatially resolved observations capture the gas breaking out of the inner galaxy, in the form of a wide-angle blueshifted outflow expanding beyond 8 kpc, with a velocity of $\sim -1000 \textrm{ km s}^{-1}$. Despite the three orders of magnitude variation in spatial scale, and a factor-of-four deceleration, the momentum fluxes remain consistent within uncertainties across all scales. These results suggest that the distinct outflow components represent the integrated history of a sustained feedback cycle from nuclear to galactic scales.

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arXiv2026

High-S/N Quasar Observations with HST/COS: Deep Fields for Spectroscopy

Hubble is still in prime observing condition for making transformative discoveries in UV astronomy. In this white paper we describe the science case for a deep (S/N>30) UV spectroscopic survey with HST/COS targeting approximately 20 QSOs at 0.5<z<1.5 at good resolution (20 km/s). This survey would capitalize on our current UV capability, produce a legacy dataset enabling community science in many areas of galactic and extragalactic research, and pioneer a path for future UV science with the Habitable Worlds Observatory. Such high-S/N spectra are largely missing from the MAST archives, and would be analogous to the deep Hubble imaging fields (HDF, UDF, Frontier Fields) that have been enormously successful and far-reaching in their science impact. This legacy dataset would enable frontier science programs in several areas, including (1) studies of the CGM and IGM at unparalleled sensitivity, covering a wide range of UV metal lines and reaching very low H I column densities of log N=12.6 and low metallicities near [Z/H]=-2, enabling precision studies of the chemical abundances, ionization, temperature, and baryon and metal budgets of the CGM and IGM; (2) diffuse gas in the Milky Way and Local Group, including high-velocity clouds and gas streams from satellite mergers; (3) AGN outflows, which would be probed in the rest-frame extreme ultraviolet (EUV), covering continuum-generation mechanisms and diagnostics of gas in accretion-disk outflows.

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arXiv2026

AGN STORM 2. XII. Ground-Based Optical Photometry and Lag Measurements of Mrk 817

We present the ground-based imaging campaign and light curves of Markarian 817 as part of the multiwavelength monitoring program AGN STORM\,2. Observations were carried out over 1.4 years in \emph{uBgVriz} filters, with a median cadence of 0.4 days in \emph{g}. Reverberation lags are measured using three methods (ICCF, JAVELIN, and PyROA) with the Swift UVW2 band (1928 Å) as the reference light curve. The ICCF centroid lags range from $3.0\pm0.8$ days for the $u$ band up to $7.9\pm1.5$ days for $z$, and are consistent with a $τ\propto λ^{4/3}$ dependence, the relation expected for lamp-post reprocessing by a Shakura-Sunyaev disk. Lags measured with the other methods are systematically shorter, and deviate from a $λ^{4/3}$ power-law spectrum at long wavelengths. The lags exceed thin-disk reprocessing predictions by factors of $\sim$3-6, similar to the ``disk size discrepancy'' seen in other Seyfert galaxies. We divide the campaign into three epochs with different levels of mean luminosity and X-ray obscuring column density and find that the lags vary by as much as a factor of 2 between epochs. The intrinsic spectral energy distribution is bluer and brighter during the first third of the campaign, and the longest continuum reverberation lags are obtained during that period. These results suggest that changes in ionizing luminosity can produce large variations in continuum lags on short timescales by altering the diffuse continuum luminosity emitted by the broad-line region and/or obscuring outflow, although changes in obscuration between the central engine and broad-line region may also contribute to the lag variations.

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arXiv2026

Novel method to trace the dark matter density profile around supermassive black holes with AGN reverberation mapping

We propose a new method to determine the dark matter density profile in the vicinity of distant supermassive black holes (SMBH) using reverberation mapping (RM) measurements of active galactic nuclei (AGN). The mapping of multiple emission lines allows the measurement of the enclosed mass within different radii from the central SMBH, which can be used to infer or constrain the dark matter density profile on sub-parsec scales. We apply a toy model based on this method to a sample of fourteen AGN to test its feasibility based on current measurements. We find that for five objects, the observed enclosed mass does grow with radii, hinting towards the presence of a dark matter component at the 1-2 $σ$ level. For these sources, we find global evidence for a universal dark matter profile with a preferred radial steepness of index $γ\sim 1.6$, consistent with the scenario expected for a dark matter spike mildly relaxed by stellar heating processes. The enclosed dark matter mass, however, is found to be significantly larger than expected. We show that the current RM based mass measurements suffer from large systematic uncertainties, that limit the effectiveness of our method. Our work emphasizes the importance of applying the recent developments in mass determination techniques to target multiple emission lines with future RM and interferometry campaigns. This provides the most direct way of constraining the dark matter density in the sub-parsec regions around extragalactic SMBHs, which is crucial to our understanding of the dynamics and nature of dark matter.

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arXiv2026

Radio Emission from Broad Absorption Line Quasars

Broad Absorption Line Quasars (BALQs) generally exhibit significant outflows that may interact with the surrounding medium, resulting in radio emission. We selected a sample of 13 powerful radio-quiet (RQ) BALQs, where the UV outflow kinetic power is measurable, and detected nine of them with the Very Large Array A configuration at 5.5 GHz and 9.0 GHz. The radio emission is mostly unresolved and is generally constrained within a scale of < 1--4 kpc. In the nine detected objects, the radio spectral slope alpha_5.5-9.0 is steep (< -0.5) in five objects and is flat or inverted (> -0.5) in four objects. We discuss how the steep-slope emission can be associated with the UV outflows, and how the flat-slope emission can be intrinsically steep but flattened by free-free absorption from the UV outflowing gas. However, we find no correlation between the radio luminosity and the estimated outflow kinetic power, which suggests that the outflows are likely not a major source of the observed radio emission. In addition, the radio loudness of these RQ BALQs is comparable to that of typical RQ quasars, implying that the UV outflows likely do not produce stronger radio emission compared to non-BALQs. Follow-up radio observations can test the free-free absorption interpretation and can be used as a new probe for outflows in AGN.

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arXiv2025

AGN STORM 2. XI. Spectroscopic reverberation mapping of the hot dust in Mrk 817

The AGN Space Telescope and Optical Reverberation Mapping 2 (STORM 2) campaign targeted Mrk 817 with intensive multi-wavelength monitoring and found its soft X-ray emission to be strongly absorbed. We present results from 157 near-IR spectra with an average cadence of a few days. Whereas the hot dust reverberation signal as tracked by the continuum flux does not have a clear response, we recover a dust reverberation radius of $\sim 90$ light-days from the blackbody dust temperature light-curve. This radius is consistent with previous photometric reverberation mapping results when Mrk 817 was in an unobscured state. The heating/cooling process we observe indicates that the inner limit of the dusty torus is set by a process other than sublimation, rendering it a luminosity-invariant `dusty wall' of a carbonaceous composition. Assuming thermal equilibrium for dust optically thick to the incident radiation, we derive a luminosity of $\sim 6 \times 10^{44}$ erg s$^{-1}$ for the source heating it. This luminosity is similar to that of the obscured spectral energy distribution, assuming a disk with an Eddington accretion rate of $\dot{m} \sim 0.2$. Alternatively, the dust is illuminated by an unobscured lower luminosity disk with $\dot{m} \sim 0.1$, which permits the UV/optical continuum lags in the high-obscuration state to be dominated by diffuse emission from the broad-line region. Finally, we find hot dust extended on scales $> 140-350$ pc, associated with the rotating disk of ionised gas we observe in spatially-resolved [SIII] $λ9531$ images. Its likely origin is in the compact bulge of the barred spiral host galaxy, where it is heated by a nuclear starburst.

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arXiv2025

DESI survey of S IV absorption outflows in quasars: Contribution to AGN feedback and comparison with [O III] emission outflows

Quasar outflows can play a crucial role in the evolution of their host galaxies through various feedback processes. This effect is expected to be particularly important when the universe was only 2-3 billion years old, during the period known as cosmic noon. By utilizing observations from the Dark Energy Spectroscopy Instrument (DESI), we conduct a survey of high-ionization quasar outflows at cosmic noon, with the aim of doubling the current sample of such outflows with distance and energetics determination. We also aim to compare these properties to those derived from spatially resolved outflows in similar quasars probed through Integral Field Spectroscopy (IFS). In a sample of 130 quasars we detect signatures of high-ionization outflows in the form of a S IV trough in eight objects. We characterize the physical conditions of these outflows by determining their total hydrogen column density ($N_H$), ionization parameter ($U_H$), and electron number density ($n_e$). The detected outflows show complex kinematic structures with a wide range in blueshifted velocities (100$-$4600 km s$^{-1}$). We locate five out of the eight outflows at distances between 240$-$5500 pc away from the central source. From the combined sample of 15 high-ionization S IV outflows at cosmic noon, we find a high fraction (up to 46 %) of them to be powerful enough to contribute significantly to multi-stage AGN feedback processes. Their mass outflow rates and kinetic luminosities are also found to be consistent with spatially resolved outflows in a luminosity and redshift matched sample of quasars. Comparison with previous spectra reveals interesting variations in some objects, with two cases of emerging high-velocity broad absorption line features with velocities of $-$8000 and $-$39,000 km s$^{-1}$. An impressive case of four line-locked Si IV outflow systems is also revealed in one of the objects.

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arXiv2025

Quasar absorption outflows on galactic scales: Insights from DESI

Absorption outflows in quasars play an important role in understanding active galactic nuclei (AGN) feedback and their influence on galaxy evolution. The unprecedented spectral data provided by the Dark Energy Spectroscopic Instrument (DESI) opens new avenues to explore these outflows. We analyze five low-ionization absorption outflow systems in four intermediate-redshift quasars ($2 < z < 3$) using the data obtained by DESI in order to characterize their physical properties and energetics, and also to assess their role in AGN feedback. We use the spectra from DESI's Early Data Release to determine the ionic column densities, total hydrogen column densities, electron number densities, and ionization parameters via photoionization modeling and absorption line analysis. We derive the outflows' distance from the AGN, and its kinematic properties: mass-flow rates, kinetic luminosity, and momentum flux. Our study identifies five distinct mini-broad absorption line outflow systems, hosted by four quasars. The identified outflows exhibit hydrogen column densities of $\log (N_H) = 20.0-20.7$[cm$^{-2}$], ionization parameters of $\log (U_H) = -2.7$ to $-2.1$, and electron number densities of $\log (n_e) =1.45-2.85$[cm$^{-2}$]. The distances of the outflows from the central source are between 4.5 to 31 kpc, and the kinetic luminosities range from $2\times10^{-6}$ to $5\times10^{-3}$ of the Eddington luminosity. The outflows in J1407 and J1032 show the largest kinetic luminosities, with momentum flux ratios ($\dot{p} / \dot{p}_{rad}$) of about 2 and 0.2, respectively. Our findings highlight the vital role of DESI data in uncovering the diversity and significance of quasar outflows in galaxy evolution.

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arXiv2025

Galactic-scale emission-line outflow from the radio-loud quasar 3C 191

Quasar feedback is routinely invoked as an indispensable ingredient in galaxy formation models. Galactic outflows are a crucial agent of quasar feedback that frequently manifest themselves in absorption and emission lines. Measuring the size and energetics of outflows based on absorption lines remains a challenge, and integral-field spectroscopy (IFS) mapping in emission lines is complementary. We present a VLT/SINFONI IFS mapping of quasar 3C 191 at $z \sim 2$, in which the outflow has been analyzed in absorption line spectroscopy. Three components are found based on the morphology and kinetics of [OIII]-emitting gas: a unshifted component which consistent with the systemic redshift and the location of the nucleus, a blueshifted in the north, and a redshifted in the south. The latter two components have velocities $\sim$ 600 km s$^{-1}$ and projected extents of 5 and 11 kpc, respectively, suggesting a biconical outflow structure. The blueshifted component's velocity is consistent with that derived from absorption lines. Using the electron density measured by the absorption lines and the luminosity and velocity of [OIII] outflow, we derive the mass outflow rate to be $\dot{M} \sim $ 9.5-13.4 M$_\odot$ yr$^{-1}$ and kinetic luminosity $\dot{E}_{\rm kin}$ ~ 2.5-3.7 $\times 10^{42}$ erg s$^{-1}$, consistent with absorption line analyses with VLT/Xshooter spectrum. The kinetic luminosity is only 0.01% of the bolometric luminosity, rendering a relatively weak outflow compared to typical expectation for effective feedback.

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arXiv2025

The distance of quasar outflows from the central source: The first consistent values from emission and absorption determinations

Measuring the distance of quasar outflows from the central source ($R$) is essential for determining their importance for AGN feedback. There are two methods to measure $R$: 1) A direct determination using spatially resolved Integral Field Spectroscopy (IFS) of the outflow in emission. 2) An indirect method which uses the absorption troughs from ionic excited states. The column density ratio between the excited and resonance states yields the outflow number density. Combined with a knowledge of the outflow's ionization parameter, $R$ can be determined. Generally, the IFS method probes $R$ range of several kpc or more, while the absorption method usually yields $R$ values of less than 1 kpc. There is no inconsistency between the two methods as the determinations come from different objects. Here we report the results of applying both methods to the same quasar outflow, where we derive consistent determinations of $R$ $\approx$ 5 kpc. This is the first time where the indirect absorption $R$ determination is verified by a direct spatially resolved IFS observation. In addition, the velocities (and energetics) from the IFS and absorption data are also found to be consistent. Therefore, these are two manifestations of the same outflow. In this paper we concentrate on the absorption $R$ determination for the outflow seen in quasar 3C 191 using VLT/X-shooter observations. We also reanalyze an older absorption determination for the outflow based on Keck/HIRES data and find that revised measurement to be consistent with ours. Our companion paper details the IFS analysis of the same object.

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arXiv2025

Physical characterization of the FeLoBAL outflow in SDSS J0932+0840: Analysis of VLT/UVES observations

Context: The study of quasar outflows is essential in understanding the connection between active galactic nuclei (AGN) and their host galaxies. We analyze the VLT/UVES spectrum of quasar SDSS J0932+0840 and identify several narrow and broad outflow components in absorption, with multiple ionization species including Fe II, which puts it among a rare class of outflows known as FeLoBALs. Aims: We study one of the outflow components to determine its physical characteristics by determining the total hydrogen column density, ionization parameter and the hydrogen number density. Through these parameters, we aim to obtain the distance of the outflow from the central source, its mass outflow rate and kinetic luminosity, and to constrain the contribution of the outflow to AGN feedback. Methods: We obtain the ionic column densities from the absorption troughs in the spectrum, and use photoionization modeling to extract the physical parameters of the outflow, including the total hydrogen column density and ionization parameter. The relative population of the observed excited states of Fe II is used to model the hydrogen number density of the outflow. Results: We use the Fe II excited states to model the electron number density ($n_e$) and hydrogen number density ($n_H$) independently and obtain $n_e$ $\simeq$ $10^{3.4}$ cm$^{-3}$ and $n_H$ $\simeq$ $10^{4.8}$ cm$^{-3}$. Our analysis of the physical structure of the cloud shows that these two results are consistent with each other. This places the outflow system at a distance of $0.7_{-0.4}^{+0.9}$ kpc from the central source, with mass flow rate ($\dot{M}$) of $43^{+65}_{-26}$ $M_\odot$ yr$^{-1}$ and kinetic luminosity ($\dot{E_k}$) of $0.7^{+1.1}_{-0.4}$ $\times$ $10^{43}$ erg s$^{-1}$.

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arXiv2024

Determining the absolute chemical abundance of nitrogen and sulfur in the quasar outflow of 3C298

Context. Quasar outflows are key players in the feedback processes that influence the evolution of galaxies and the intergalactic medium. The chemical abundance of these outflows provides crucial insights into their origin and impact. Aims. To determine the absolute abundances of nitrogen and sulfur and the physical conditions of the outflow seen in quasar 3C298. Methods. We analyze archival spectral data from the Hubble Space Telescope (HST) for 3C298. We measure Ionic column densities from the absorption troughs and compare the results to photoionization predictions made by the Cloudy code for three different spectral energy distributions (SED), including MF87, UVsoft, and HE0238 SEDs. We also calculate the ionic column densities of excited and ground states of N iii to estimate the electron number density and location of the outflow using the Chianti atomic database. Results. The MF87, UVsoft, and HE0238 SEDs yield nitrogen and sulfur abundances at super-solar, solar, and sub-solar values, respectively, with a spread of 0.4 to 3 times solar. Additionally, we determined an electron number density of log(ne) greater than 3.3 cm-3, with the outflow possibly extending up to a maximum distance of 2.8 kpc. Conclusions. Our results indicate solar metallicity within a 60 percent uncertainty range, driven by variations in the chosen SED and photoionization models. This study underscores the importance of SEDs impact on determining chemical abundances in quasars outflows. These findings highlight the necessity of considering a wider range of possible abundances, spanning from sub solar to super solar values.

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arXiv2024

AGN STORM 2: X. The origin of the interband continuum delays in Mrk 817

The local (z=0.0315) AGN Mrk 817, was monitored over more than 500 days with space-borne and ground-based instruments as part of a large international campaign AGN STORM 2. Here, we present a comprehensive analysis of the broad-band continuum variations using detailed modeling of the broad line region (BLR), several types of disk winds classified by their optical depth, and new numerical simulations. We find that diffuse continuum (DC) emission, with additional contributions from strong and broad emission lines, can explain the continuum lags observed in this source during high and low luminosity phases. Disk illumination by the variable X-ray corona contributes only a small fraction of the observed continuum lags. Our BLR models assume radiation pressure-confined clouds distributed over a distance of 2-122 light days. We present calculated mean-emissivity radii of many emission lines, and DC emission, and suggest a simple, transfer-function-dependent method that ties them to cross-correlation lag determinations. We do not find clear indications for large optical depth winds but identify the signature of lower column density winds. In particular, we associate the shortest observed continuum lags with a combination of tau(1 Ryd) approx. 2 wind and a partly shielded BLR. Even smaller optical depth winds may be associated with X-ray absorption features and with noticeable variations in the width and lags of several high ionization lines like HeII and CIV. Finally, we demonstrate the effect of torus dust emission on the observed lags in the i and z bands.

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arXiv2024

AGN STORM 2. VII. A Frequency-resolved Map of the Accretion Disk in Mrk 817: Simultaneous X-ray Reverberation and UVOIR Disk Reprocessing Time Lags

X-ray reverberation mapping is a powerful technique for probing the innermost accretion disk, whereas continuum reverberation mapping in the UV, optical, and infrared (UVOIR) reveals reprocessing by the rest of the accretion disk and broad-line region (BLR). We present the time lags of Mrk 817 as a function of temporal frequency measured from 14 months of high-cadence monitoring from Swift and ground-based telescopes, in addition to an XMM-Newton observation, as part of the AGN STORM 2 campaign. The XMM-Newton lags reveal the first detection of a soft lag in this source, consistent with reverberation from the innermost accretion flow. These results mark the first simultaneous measurement of X-ray reverberation and UVOIR disk reprocessing lags$\unicode{x2013}$effectively allowing us to map the entire accretion disk surrounding the black hole. Similar to previous continuum reverberation mapping campaigns, the UVOIR time lags arising at low temporal frequencies are longer than those expected from standard disk reprocessing by a factor of 2-3. The lags agree with the anticipated disk reverberation lags when isolating short-timescale variability, namely timescales shorter than the H$β$ lag. Modeling the lags requires additional reprocessing constrained at a radius consistent with the BLR size scale inferred from contemporaneous H$β$-lag measurements. When we divide the campaign light curves, the UVOIR lags show substantial variations, with longer lags measured when obscuration from an ionized outflow is greatest. We suggest that, when the obscurer is strongest, reprocessing by the BLR elongates the lags most significantly. As the wind weakens, the lags are dominated by shorter accretion disk lags.

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arXiv2024

AGN STORM 2: VIII. Investigating the Narrow Absorption Lines in Mrk 817 Using HST-COS Observations

We observed the Seyfert 1 galaxy Mrk817 during an intensive multi-wavelength reverberation mapping campaign for 16 months. Here, we examine the behavior of narrow UV absorption lines seen in HST/COS spectra, both during the campaign and in other epochs extending over 14 years. We conclude that while the narrow absorption outflow system (at -3750 km/s with FWHM=177 km/s) responds to the variations of the UV continuum as modified by the X-ray obscurer, its total column density (logNH =19.5 cm-2) did not change across all epochs. The adjusted ionization parameter (scaled with respect to the variations in the Hydrogen ionizing continuum flux) is log UH =-1.0. The outflow is located at a distance smaller than 38 parsecs from the central source, which implies a hydrogen density of nH > 3000 cm-3. The absorption outflow system only covers the continuum emission source and not the broad emission line region, which suggests that its transverse size is small (< 1e16 cm), with potential cloud geometries ranging from spherical to elongated along the line of sight.

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arXiv2024

AGN STORM 2: IX. Studying the Dynamics of the Ionized Obscurer in Mrk 817 with High-resolution X-ray Spectroscopy

We present the results of the XMM-Newton and NuSTAR observations taken as part of the ongoing, intensive multi-wavelength monitoring program of the Seyfert 1 galaxy Mrk 817 by the AGN Space Telescope and Optical Reverberation Mapping 2 (AGN STORM 2) Project. The campaign revealed an unexpected and transient obscuring outflow, never before seen in this source. Of our four XMM-Newton/NuSTAR epochs, one fortuitously taken during a bright X-ray state has strong narrow absorption lines in the high-resolution grating spectra. From these absorption features, we determine that the obscurer is in fact a multi-phase ionized wind with an outflow velocity of $\sim$5200 km s$^{-1}$, and for the first time find evidence for a lower ionization component with the same velocity observed in absorption features in the contemporaneous HST spectra. This indicates that the UV absorption troughs may be due to dense clumps embedded in diffuse, higher ionization gas responsible for the X-ray absorption lines of the same velocity. We observe variability in the shape of the absorption lines on timescales of hours, placing the variable component at roughly 1000 $R_g$ if attributed to transverse motion along the line of sight. This estimate aligns with independent UV measurements of the distance to the obscurer suggesting an accretion disk wind at the inner broad line region. We estimate that it takes roughly 200 days for the outflow to travel from the disk to our line of sight, consistent with the timescale of the outflow's column density variations throughout the campaign.

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arXiv2024

Extreme FeLoBAL Outflow in the VLT/UVES Spectrum of Quasar SDSS J1321-0041

Context. Quasar outflows are often analyzed to determine their ability to contribute to active galactic nucleus (AGN) feedback. We identified a broad absorption line (BAL) outflow in the VLT/UVES spectrum of the quasar SDSS J1321-0041. The outflow shows troughs from Fe II, and is thus categorized as an FeLoBAL. This outflow is unusual among the population of FeLoBAL outflows, as it displays C II and Si II BALs. Aims. Outflow systems require a kinetic luminosity above $\sim0.5\%$ of the quasar's luminosity to contribute to AGN feedback. For this reason, we analyzed the spectrum of J1321-0041 to determine the outflow's kinetic luminosity, as well as the quasar's bolometric luminosity. Methods. We measured the ionic column densities from the absorption troughs in the spectrum and determined the Hydrogen column density and ionization parameter using those column densities as our constraints. We also determined the electron number density, $n_e$, based on the ratios between the excited-state and resonance-state column densities of Fe II and Si II. This allowed us to find the distance of the outflow from its central source, as well as its kinetic luminosity. Results. We determined the kinetic luminosity of the outflow to be $8.4^{+13.7}_{-5.4}\times 10^{45}\text{ erg s}^{-1}$, and the quasar's bolometric luminosity to be $1.72\pm0.13\times10^{47}\text{ erg s}^{-1}$, resulting in a ratio of $\dot{E}_k/L_{Bol}=4.8^{+8.0}_{-3.1}\%$. We conclude that this outflow has a sufficiently high kinetic luminosity to contribute to AGN feedback.

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arXiv2024

BAL Outflow in Quasar B0254-3327B: Analysis and Comparison with Other Extreme UV Outflows

We have identified a broad absorption line (BAL) outflow in the HST/STIS spectrum of the quasar QSO B0254-3327B at velocity $v=-3200\text{ km s$^{-1}$}$. The outflow has absorption troughs from ions such as Ne VIII, Na IX, Si XII, and Ne V. We also report the first detection of S XIV absorption troughs, implying very high ionization. Via measurement of the ionic column densities, photoionization analysis, and determination of the electron number density of the outflow, we found the kinetic luminosity of the outflow system to be up to $\sim1\%$ of the quasar's Eddington luminosity, or $\sim5\%$ of the bolometric luminosity, making it a potential contributor to AGN feedback. A solution with two ionization phases was needed, as a single phase was not sufficient to satisfy the constraints from the measured ionic column densities. We find that the ionization parameter of the very high-ionization phase of the outflow is within the expected range of an X-ray warm absorber. We also examined the physical properties of the outflow of Q0254-334 along with previously studied extreme UV outflows, with a total sample of 24 outflow systems, finding a weak negative correlation between outflow velocity and distance from the central source, with larger distances corresponding to slower velocities. The very high-ionization phase of the Q0254-334 outflow has one of the highest ionization parameters of UV absorption outflows to date, which we attribute to the presence of S XIV.

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