2001/08/23 by Bassem M. Sabra, Fred Hamann, Sabra, Bassem M. +1
Physics and Astronomy · #Astrophysics (astro-ph) #FOS: Physical sciences #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0108383
Accepted for publication in the Astrophysical Journal
arxiv created 2001/09/12 · arxiv updated 2009/12/01
We present Chandra observations of the radio-quiet Broad Absorption Line (BAL) QSO PG 1254+047. We find that it is a weak X-ray source, with a total of 44± 7 photons measured in 36 ksec across the observed energy range 0.7 - 6.0 keV. Its X-ray weakness is consistent with the known correlation between αox and the strength of the UV absorption lines. The spectral energy distribution suggests that PG 1254+047 is intrinsically X-ray weak, in addition to being heavily X-ray absorbed. The X-ray absorption column density is NH > 1023 cm-2 for neutral gas, while the intrinsic (unabsorbed) emission spectrum has αox > 2. The data are fit best by including an ionized (rather than neutral) absorber, with column density NH \gtrsim 2× 1023 cm-2. The degree of ionization is consistent with the UV BALs, as is the total column density if the strongest UV lines are saturated. If the X-ray absorber forms in a wind that is radiatively accelerated to the BAL velocities, then the wind must be launched from a radius of about 1016 cm with a mass loss rate of ∼ 1 M_\odot yr-1.