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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 (ne) and hydrogen number density (nH) independently and obtainedne≃ 103.4cm−3andnH≃ 104.8cm−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 (Ėk) of 0.7−0.4+1.1× 1043erg s−1. This is 0.5−0.3+0.7× 10−4of the Eddington luminosity (LEdd) of the quasar, and we thus conclude that this outflow is not powerful enough to contribute significantly toward AGN feedback.
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This content will become publicly available on April 3, 2026
The Distance of Quasar Outflows from the Central Source: The First Consistent Values from Emission and Absorption Determinations
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.
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- Award ID(s):
- 2106249
- PAR ID:
- 10613910
- Publisher / Repository:
- The Astrophysical Journal
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 983
- Issue:
- 1
- ISSN:
- 0004-637X
- Page Range / eLocation ID:
- 31
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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