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arXiv · 2208.01210

Effect of radiation drag on the line-force-driven winds

Bei-Chuan Wang·Xiao-Hong Yang·De-Fu Bu·Shu-Su Huang
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Abstract

Ultra-fast outflows (UFOs) with mildly relativistic velocities are measured using the X-ray spectra of radio-quiet and -loud active galactic nuclei (AGNs). In general, UFOs are believed to be generated from the accretion disk around a black hole (BH). A line-force driving model is suggested to be the mechanism to drive UFOs from the accretion disk. In this paper, we use the non-hydrodynamic approach to examine the influences of radiation-drag effects on the line-force-driven winds generated from the accretion disk. We find that the radiation-drag effects can significantly weaken the line-force-driven winds. Compared with the case without the radiation-drag effects, when the radiation-drag effects are considered, the maximum speed of winds is reduced by $\sim$60\%--70\%, the mass outflow rate is reduced by $\sim$50\%--80\%, and the kinetic power is reduced by about an order of magnitude. The radiation-drag effects narrow the area where the winds are generated.

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Bei-Chuan Wang, Xiao-Hong Yang, De-Fu Bu, Shu-Su Huang. 2022-08-02. Effect of radiation drag on the line-force-driven winds. https://doi.org/10.1093/mnras%2Fstac2203

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