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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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This content will become publicly available on October 29, 2026
Balmer Absorption in Iron Low-ionization Broad Absorption Line Quasars
Abstract While Civis the most common absorption line in broad absorption line quasar spectra, Balmer absorption lines (BALs) are among the rarest. We present analysis of Balmer absorption in a sample of 14 iron low-ionization BAL quasars (FeLoBALQs); eight are new identifications. We measured velocity offset, width, and apparent optical depth. The partial covering that is ubiquitous in BAL quasar spectra alters the measured Balmer optical depth ratios; accounting for this, we estimated the true H(n= 2) column density. We found the anticipated correlation between Eddington ratio and outflow speed, but it is weak in this sample because nearly all of the objects have the low outflow speeds characterizing loitering outflow FeLoBAL quasars, objects that are also found to have low accretion rates. Measurements ofdN/dv, the differential column density with respect to the outflow speed, are anticorrelated with the luminosity and Eddington ratio: the strongest absorption is observed at the lowest speeds in the lowest-luminosity objects. The absorption line width is correlated withαoi, theFλpoint-to-point slope between 5100 Å and 3μm. This parameter is strongly correlated with the Eddington ratio among low-redshift quasars. BALs have been recently found in the spectra of little red dots (LRDs), a class of high-redshift objects discovered by JWST. We note suggestive similarities between LRDs and FeLoBAL quasars in the emission-line shape, the presence of steep reddening and a scattered blue continuum, the lack of hot dust emission, and X-ray weakness.
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- Award ID(s):
- 2006771
- PAR ID:
- 10649107
- Publisher / Repository:
- The Astrophysical Journal
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 993
- Issue:
- 1
- ISSN:
- 0004-637X
- Page Range / eLocation ID:
- 129
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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