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arXiv · 2106.06567

The X-Rays wind connection in PG 2112+059

C. Saez·W. N. Brandt·F. Bauer·G. Chartas·T. Misawa·F. Hamann·S. Gallagher
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Abstract

We study the connection between the X-ray and 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 BALs 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.

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C. Saez, W. N. Brandt, F. Bauer, G. Chartas, T. Misawa, F. Hamann, S. Gallagher. 2021-06-11. The X-Rays wind connection in PG 2112+059. https://doi.org/10.1093/mnras/stab1706

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