Supercritical Disk Accretion with Mass Loss

نویسنده

  • Galina V. Lipunova
چکیده

We consider supercritical accretion onto a compact object when the accretion rate exceeds its value derived from the Eddington limit: ṀEdd = LEdd/c . We use the scenario that was proposed by Shakura and Sunyaev (1973) for the supercritical regime, according to which matter flows out of the gas-disk surface under radiation pressure. An analytic solution of the accretion-disk structure is obtained for this scenario by using classical equations. An attempt is made to construct a model for nonconservative supercritical accretion with advection. To this end, we develop a numerical scheme for calculating the structure of an advective disk with mass outflow. The goal of solving the problem of a supercritical disk with mass loss is to explain accreting sources with outflowing envelopes, for example, SS 433 and galactic nuclei. The structure and observational manifestations of the envelope which forms around a supercritical disk are considered by taking into account bremsstrahlung absorption and Thomson scattering of photons.

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تاریخ انتشار 1999