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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,ne, 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 ofĖk/LBol = 4.8−3.1+8.0%. We conclude that this outflow has a sufficiently high kinetic luminosity to contribute to AGN feedback.
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The Farthest Quasar Mini-Broad Absorption Line Outflow from Its Central Source: Very Large Telescope/UVES Observation of SDSS J0242+0049
Abstract We analyze Very Large Telescope/UVES observations of the quasar SDSS J024221.87+004912.6. We identify four absorption outflow systems: a Civbroad absorption line (BAL) atv≈ −18,000 km s−1and three narrower low-ionization systems with centroid velocities ranging from –1200 to –3500 km s−1. These outflows show similar physical attributes to the [Oiii] outflows studied by Liu et al. (2013). We find that two of the systems are energetic enough to contribute to active galactic nucleus feedback, with one system reaching above 5% of the quasar’s Eddington luminosity. We also find that this system is at a distance of 67 kpc away from the quasar, the farthest detected mini-BAL absorption outflow from its central source to date. In addition, we examine the time-variability of the BAL and find that its velocity monotonically increases, while the trough itself becomes shallower over time.
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- Award ID(s):
- 2106249
- PAR ID:
- 10364067
- Publisher / Repository:
- DOI PREFIX: 10.3847
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 927
- Issue:
- 2
- ISSN:
- 0004-637X
- Format(s):
- Medium: X Size: Article No. 176
- Size(s):
- Article No. 176
- Sponsoring Org:
- National Science Foundation
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