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Abstract Measuring the distance of quasar outflows from the central source (R) is essential for determining their importance for active galactic nucleus feedback. There are two methods to measureR: (1) a direct determination using spatially resolved integral field spectroscopy (IFS) of the outflow in emission and (2) an indirect method that 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,Rcan be determined. Generally, the IFS method probes anRrange of several kiloparsecs or more, while the absorption method usually yieldsRvalues 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 ofR≈ 5 kpc. This is the first time that the indirect absorptionRdetermination is verified by a direct spatially resolved IFS observation. In addition, the velocities (and energetics) from the IFS and absorption data are found to be consistent. Therefore, these are two manifestations of the same outflow. In this paper we concentrate on the absorptionRdetermination for the outflow seen in quasar 3C 191 using Very Large Telescope/X-shooter observations. We also reanalyze an older absorption determination for the outflow based on Keck/High Resolution Echelle Spectrometer data and find the revised measurement to be consistent with ours. Our companion paper details the IFS analysis of the same object. 

Context.The study of quasar outflows is essential for understanding the connection between active galactic nuclei (AGN) and their host galaxies. We analyzed the VLT/UVES spectrum of quasar SDSS J0932+0840 and identified several narrow and broad outflow components in absorption, with multiple ionization species including Fe II. This places it among the rare class of outflows known as iron low-ionization broad absorption line outflows (FeLoBALs). Aims.We studied one of the outflow components to determine its physical characteristics by determining the total hydrogen column density, the ionization parameter, and the hydrogen number density. Through these parameters, we obtained the distance of the outflow from the central source, its mass outflow rate, and its kinetic luminosity, and we constrained the contribution of the outflow to the AGN feedback. Methods.We obtained the ionic column densities from the absorption troughs in the spectrum and used 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 IIwas used to model the hydrogen number density of the outflow. Results.We used the Fe IIexcited states to model the electron number density (n_e) and hydrogen number density (n_H) independently and obtainedn_e≃ 10^3.4cm⁻³andn_H≃ 10^4.8cm⁻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^+0.9kpc from the central source, with a mass flow rate (Ṁ) of 43₋₂₆⁺⁶⁵ M_⊙yr⁻¹and a kinetic luminosity (Ė_k) of 0.7_−0.4^+1.1× 10⁴³erg s⁻¹. This is 0.5_−0.3^+0.7× 10⁻⁴of the Eddington luminosity (L_Edd) of the quasar, and we thus conclude that this outflow is not powerful enough to contribute significantly toward AGN feedback. 

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 outfow is unusual among the population of FeLoBAL outflows, as it displays C IIand Si IIBALs. Aims.Outflow systems require a kinetic luminosity above ∼0.5% 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 IIand 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_−5.4^+13.7 × 10⁴⁵ erg s⁻¹and the quasar’s bolometric luminosity to be 1.72 ± 0.13 × 10⁴⁷ erg s⁻¹, resulting in a ratio ofĖ_k/L_Bol = 4.8_−3.1^+8.0%. We conclude that this outflow has a sufficiently high kinetic luminosity to contribute to AGN feedback. 

ABSTRACT We have identified a broad absorption line (BAL) outflow in the HST/STIS spectrum of the quasar QSO B0254-3327B at velocity v = −3200 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 ∼1 per cent of the quasar’s Eddington luminosity, or ∼5 per cent 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. 

Abstract We observed the Seyfert 1 galaxy Mrk 817 during an intensive multiwavelength reverberation mapping campaign for 16 months. Here, we examine the behavior of narrow UV absorption lines seen in the Hubble Space Telescope/Cosmic Origins Spectrograph spectra, both during the campaign and in other epochs extending over 14 yr. We conclude that, while the narrow absorption outflow system (at −3750 km s⁻¹with FWHM = 177 km s⁻¹) responds to the variations of the UV continuum as modified by the X-ray obscurer, its total column density (logN_H= 19.5 ${}_{-0.13}^{+0.61}$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 logU_H= −1.0 ${}_{-0.3}^{+0.1}$. The outflow is located at a distance smaller than 38 pc from the central source, which implies a hydrogen density ofn_H> 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 (< 10¹⁶cm), with potential cloud geometries ranging from spherical to elongated along the line of sight.