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arXiv · 1201.3627

PHL 1811 Analogs: A Population of X-ray Weak Quasars

Jianfeng Wu·W. N. Brandt·Patrick B. Hall·Robert R. Gibson·Gordon T. Richards·Donald P. Schneider·Ohad Shemmer·Dennis W. Just·Sarah J. Schmidt
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Abstract

We report on a population of X-ray weak quasars with similar UV emission-line properties to those of the remarkable quasar PHL 1811. All radio-quiet PHL 1811 analogs are notably X-ray weak by a mean factor of ~13, with hints of heavy X-ray absorption. Correlations between the X-ray weakness and UV emission-line properties suggest that PHL 1811 analogs may have extreme wind-dominated broad emission-line regions (BELRs). We propose an AGN geometry that can potentially unify the PHL 1811 analogs and the general population of weak-line quasars.

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Jianfeng Wu, W. N. Brandt, Patrick B. Hall, Robert R. Gibson, Gordon T. Richards, Donald P. Schneider, Ohad Shemmer, Dennis W. Just, Sarah J. Schmidt. 2012-01-17. PHL 1811 Analogs: A Population of X-ray Weak Quasars. https://arxiv.org/abs/1201.3627

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