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An Exploratory Chandra survey of Large Bright Quasar Survey broad absorption line QSOs

S. C. Gallagher·W. N. Brandt·G. Chartas·R. M. Sambruna
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Abstract

We are in the process of obtaining a complete sample of exploratory X-ray observations of broad absorption line (BAL) QSOs from the Large Bright Quasar Survey (LBQS). This survey is composed of short (5-7 ks) Chandra ACIS-S3 observations designed to significantly constrain X-ray fluxes and hardness ratios. Our sample avoids the selection biases of some previous surveys while providing X-ray data of similar quality. Of 17 BAL QSOs observed to date, 13 are detected. In general, our results are consistent with absorption as the primary cause of X-ray weakness in BAL QSOs. As found by Green et al. (2001), those BAL QSOs with low-ionization absorption lines are found to be notably X-ray weaker than BAL QSOs with only high ionization lines.

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S. C. Gallagher, W. N. Brandt, G. Chartas, R. M. Sambruna. 2002-05-17. An Exploratory Chandra survey of Large Bright Quasar Survey broad absorption line QSOs. https://arxiv.org/abs/astro-ph/0205303

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