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arXiv · 1711.02238

On the wind production from hot accretion flows with different accretion rates

De-Fu Bu·Zhao-Ming Gan
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Abstract

We perform two-dimensional simulations to study how the wind strength changes with accretion rate. We take into account bremsstrahlung, synchrotron radiation and the Comptonization. We find that when the accretion rate is low, radiative cooling is not important, the accretion flow is hot accretion flow. For the hot accretion flow, wind is very strong. The mass flux of wind can be $\sim 50\%$ of the mass inflow rate. When the accretion rate increases to a value at which radiative cooling rate is roughly equal to or slightly larger than viscous heating rate, cold clumps can form around the equatorial plane. In this case, the gas pressure gradient force is small and wind is very weak. Our results may be useful for the sub-grid model of active galactic nuclear feedback study.

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De-Fu Bu, Zhao-Ming Gan. 2017-11-07. On the wind production from hot accretion flows with different accretion rates. https://doi.org/10.1093/mnras%2Fstx2894

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