Systematic Construction of Exact MHD models for Astrophysical Winds and Jets
نویسنده
چکیده
By a systematic method we construct general classes of exact and selfconsistent axisymmetric MHD solutions describing flows which originate at the near environment of a central gravitating astrophysical object. The unifying scheme contains two large groups of exact MHD outflow models, (I) meridionally self-similar ones with spherical critical surfaces and (II) radially self-similar models with conical critical surfaces. The classification includes known polytropic models, such as the classical Parker model of a stellar wind and the Blandford and Payne (1982) model of a disk-wind; it also contains nonpolytropic models, such as those of winds/jets in Sauty and Tsinganos (1994), Lima et al (1996) and Trussoni et al (1997). Besides the unification of these known cases under a common scheme, several new classes emerge and some are briefly analysed; they could be explored for a further understanding of the physical properties of MHD outflows from various magnetized and rotating astrophysical objects in stellar or galactic systems.
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