Magnetically Arrested Disk : an Energetically Efficient Accretion Flow

  title={Magnetically Arrested Disk : an Energetically Efficient Accretion Flow},
  author={Ramesh Narayan and I. V. Igumenshchev and Marek Abramowicz},
  journal={Publications of the Astronomical Society of Japan},
OAK-B135 We consider an accretion flow model originally proposed by Bisnovatyi-Kogan and Ruzmaikin (1974), which has been confirmed in recent 3D MHD simulations. In this model, the accreting gas drags in a strong poloidal magnetic field to the center such that the accumulated field disrupts the axisymmetric accretion flow at a relatively large radius. Inside the disruption radius, the gas accretes as discrete blobs or streams with a velocity much less than the free-fall velocity. Almost the… 

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