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arXiv · 1807.03868

No evidence for an Eddington-ratio dependence of X-ray weakness in BALQSOs

Fabio Vito·William Nielsen Brandt·Bin Luo·Ohad Shemmer·Cristian Vignali·Roberto Gilli
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Abstract

Several works have studied the relation between X-ray, UV, and wind properties in broad absorption line quasars (BALQSOs), generally concluding that the formation of strong winds is tightly connected with the suppression of the ionizing EUV/X-ray emission. The Eddington ratio ($λ_{Edd}$), which measures the accretion rate, is also known to be related with outflow and emission-line properties in the general quasar population. Moreover, models describing quasar accretion depend on $λ_{Edd}$, which can thus possibly affect the relative production of accelerating UV and ionizing EUV/X-ray radiation. In this work, for the first time, we investigated whether BALQSO X-ray properties are related with the Eddington ratio. We selected a sample of 30 BALQSOs with accurate measurements of black-hole mass and BAL properties from the literature, and we complemented it with 4 additional BALQSOs we observed with \xmm\, to populate the low and high Eddington-ratio regimes. We did not find evidence for a strong relation between $λ_{Edd}$ and X-ray suppression, which however shows a significant correlation with the strength of the UV absorption features. These findings are confirmed also by considering a sample of mini-BALQSOs collected from the literature.

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Fabio Vito, William Nielsen Brandt, Bin Luo, Ohad Shemmer, Cristian Vignali, Roberto Gilli. 2018-07-10. No evidence for an Eddington-ratio dependence of X-ray weakness in BALQSOs. https://doi.org/10.1093/mnras%2Fsty1765

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