Physics and Astronomy Publications
ULTRAVIOLET/X-RAY VARIABILITY AND THE EXTENDED X-RAY EMISSION OF THE RADIO-LOUD BROAD ABSORPTION LINE QUASAR PG 1004+130
Document Type
Article
Publication Date
6-20-2015
Journal
Astrophysical Journal
Volume
806
Issue
2
URL with Digital Object Identifier
10.1088/0004-637X/806/2/210
Abstract
We present the results of recent Chandra, XMM-Newton, and Hubble Space Telescope observations of the radio-loud (RL), broad absorption line (BAL) quasar PG 1004+130. We compare our new observations to archival X-ray and UV data, creating the most comprehensive, high signal-to-noise, multi-epoch, spectral monitoring campaign of a RL BAL quasar to date. We probe for variability of the X-ray absorption, the UV BAL, and the X-ray jet, on month-year timescales. The X-ray absorber has a low column density of NH = 8 × 1020 - 4 × 1021 cm-2 when it is assumed to be fully covering the X-ray emitting region, and its properties do not vary significantly between the four observations. This suggests that the observed absorption is not related to the typical "shielding gas" commonly invoked in BAL quasar models, but is likely due to material further from the central black hole. In contrast, the C iv BAL shows strong variability. The equivalent width (EW) in 2014 is EW = 11.24 ± 0.56 Å, showing a fractional increase of ΔEW / 〈EW〉 = 1.16 ± 0.11 from the 2003 observation, 3183 days earlier in the rest-frame. This places PG 1004 + 130 among the most highly variable BAL quasars. By combining Chandra observations we create an exposure that is 2.5 times deeper than studied previously, with which to investigate the nature of the X-ray jet and extended diffuse X-ray emission. An X-ray knot, likely with a synchrotron origin, is detected in the radio jet ∼8"(30 kpc) from the central X-ray source with a spatial extent of ∼4"(15 kpc). No similar X-ray counterpart to the counterjet is detected. Asymmetric, non-thermal diffuse X-ray emission, likely due to inverse Compton scattering of Cosmic Microwave Background photons, is also detected.