The structure of protosolar accretion disk

The structure of protosolar accretion disk during the stage of viscous evol ution is calculated. The standard, steady-state model of accretion disk is adopted to describe the turbulent viscosity in the disk. Radial energy tran sport is neglected, and the vertical structure is treated as an one-dimensi onal problem. It is assumed that the disk performs Keplerian differential r otation and is in hydrostatic and thermal equilibrium. The disk is heated b y viscous dissipation, and energy is transported outward by convection and radiation. The results show that the temperature-sensitive opacity is an im portant factor for the structure of the disk. The protosolar accretion disk is a cold and thin disk. The boundary of instability of heat convection in the disk moves from outer to inner regions and from upper to lower layers. Formation of planets should begin in the region where convection terminate s.