Three-component accretion flows around black holes and implications

Based on the dynamics of accretion flow theory and outermost accretion boundary conditions, we have constructed a modified version of the two-zone hybrid disk model (Esin et al. 1997). This modified version has three components of accretion flows, including a third component parallel to the two-zone hybrid disk flow. In two-dimensional study, we investigated two parallel flows which gives two types of the disk structures dependent on shocked or smooth low angular momentum flow above the equatorial plane, which sandwiches high angular momentum flow (ADAF-type or Keplerian disk type) on the equatorial plane. This new version disk model is expected to suitably explain the important properties of the black hole X-ray binaries, such as counter-clockwise traversal in the hardness-intensity diagram, hysteresis-like effect including rising and decaying paths, failed outbursts, and anomalous soft state. The difference between the dynamical timescales of the parallel flows of the modified model can suitably explain the hysteresis-like effect in the outbursts.