Browsing by Author "Chamberlain, Carter"

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    BAL phosphorus abundance and evidence for immense ionic column densities in quasar outflows: vlt/x-shooter observations of quasar SDSS J1512+1119
    Borguet, Benoit C. J.; Edmonds, Douglas; Arav, Nahum; Benn, C.; Chamberlain, Carter (IOP Publishing Ltd., 2012-10)
    We present spectroscopic analysis of the broad absorption line (BAL) outflow in quasar SDSS J1512+1119. In particular, we focus our attention on a kinematic component in which we identify P V and S IV/S IV* absorption troughs. The shape of the unblended phosphorus doublet troughs and the three S IV/S IV* troughs allow us to obtain reliable column density measurements for these two ions. Photoionization modeling using these column densities and those of He I* constrain the abundance of phosphorus to the range of 0.5-4 times the solar value. The total column density, ionization parameter, and metallicity inferred from the P V and S IV column densities lead to large optical depth values for the common transition observed in BAL outflows. We show that the true C IV optical depth is similar to 1000 times greater in the core of the absorption profile than the value deduced from its apparent optical depth.
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    Major contributor to AGN feedback: VLT X-shooter observations of S iv BALQSO outflows
    Borguet, Benoit C. J.; Arav, Nahum; Edmonds, Douglas; Chamberlain, Carter; Benn, C. (IOP Publishing Ltd., 2013-01)
    We present the most energetic BALQSO outflow measured to date, with a kinetic luminosity of at least 1046 erg s(-1), which is 5% of the bolometric luminosity of this high Eddington ratio quasar. The associated mass-flow rate is 400 solar masses per year. Such kinetic luminosity and mass-flow rate should provide strong active galactic nucleus feedback effects. The outflow is located at about 300 pc from the quasar and has a velocity of roughly 8000 km s-1. Our distance and energetic measurements are based in large part on the identification and measurement of S iv and S IV* broad absorption lines (BALs). The use of this high-ionization species allows us to generalize the result to the majority of high-ionization BALQSOs that are identified by their C iv absorption. We also report the energetics of two other outflows seen in another object using the same technique. The distances of all three outflows from the central source (100-2000 pc) suggest that we observe BAL troughs much farther away from the central source than the assumed acceleration region of these outflows (0.01-0.1 pc).