Effective Inner Radius of Tilted Black Hole Accretion Disks

摘要: One of the primary means determining spin a an astrophysical black hole is by actually measuring inner radius r in surrounding accretion disk and using that to infer a. By comparing number different estimates from simulations tilted disks with differing spins, we show such procedure can give quite wrong answers. Over range 0 ≤ a/M 0.9, find that, for moderately thick (H/r ~ 0.2) modest tilt (15°), nearly independent spin. This result likely dependent on tilt, larger tilts, it may even be would increase increasing In opposite limit, confirm through numerical untilted limit zero recovers approximately expected dependence