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Monthly Notices of the Royal Astronomical Society





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We study the connection between the X-ray and ultraviolet (UV) properties of the broad absorption line (BAL) wind in the highly X-ray variable quasar PG 2112+059 by comparing Chandra-ACIS data with contemporaneous UV HST/STIS spectra in three different epochs. We observe a correlation whereby an increase in the equivalent widths (EWs) of the BALs is accompanied by a redder UV spectrum. The growth in the BAL EWs is also accompanied by a significant dimming in soft X-ray emission (≳2, keV), consistent with increased absorption. Variations in the hard X-ray emission (≳2, keV) are only accompanied by minor spectral variations of the UV-BALs and do not show significant changes in the EW of BALs. These trends suggest a wind-shield scenario where the outflow inclination with respect to the line of sight is decreasing and/or the wind mass is increasing. These changes elevate the covering fraction and/or column densities of the BALs and are likely accompanied by a nearly contemporaneous increase in the column density of the shield.


This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society©: 2021 Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.

Citation of this paper:

C Saez, W N Brandt, F E Bauer, G Chartas, T Misawa, F Hamann, S C Gallagher, The X-rays wind connection in PG 2112+059, Monthly Notices of the Royal Astronomical Society, Volume 506, Issue 1, September 2021, Pages 343–356,

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