Formation of Stationary Magnetohydrodynamic Outflows from a Disk by Time-dependent Simulations
نویسندگان
چکیده
We report the discovery of a family of stationary magnetohydrodynamic (MHD) outÑows from a disk found by time-dependent, axisymmetric MHD simulations. The initial poloidal magnetic Ðeld threading the disk was taken to be a tapered monopole Ðeld, with the Ðeld strength on the disk decreasing outwardly to small values. At the disk surface, matter was given a small initial push with a speed less than the slow magnetosonic speed. In the simulations, the outÑowing matter is observed to be accelerated by magnetic and centrifugal forces up to velocities in excess of the fast magnetosonic speed and in excess of the escape speed. Subject headings : ISM: jets and outÑows È MHD
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