The Long-term X-ray Variability Of Broad Absorption Line Quasars

We analyze X-ray the variability of eleven broad absorption line (BAL) quasars. This sample has coverage with multiple X-ray observations including Chandra, XMM-Newton , BeppoSAX , ASCA, ROSAT , and Einstein. In seven out of the eleven sources we have analyzed new short Chandra observations (5-7 ks) suitable for searching for any strong X-ray variability. Our X-ray coverage on each source spans approximately six X-ray observations with a rest-frame time of 13.7 years. We find evidence of X-ray variability (with significance >99%) in three sources (PG 1001+054, PG 1004+130, and PG 2112+059). The flux amplitude of the variability is 3.3 ± 1.2, 1.50 ± 0.06, and 10.8 ± 2.6 with rest-frame times scales of approximately 5.8, 1.4, and 0.5 years for PG 1001+054, PG 1004+130, and PG 2112+059 respectively. For PG 1004+130 and PG 2112+059 we also find significant (with significance >99%) spectral X-ray variability associated to their flux variability. Additionally, we report for the first time an X-ray detection of IRAS 14026+4341 with statistical significance of ≈5σ in its new Chandra observation.