2002/05/14 by C. Sauty, E. Trussoni, K. Tsinganos · 2 citations
Physics and Astronomy · #Astrophysics and Star Formation Studies #Ionosphere and magnetosphere dynamics #Solar and Space Plasma Dynamics #astro-ph
paper · pdf · doi:10.1051/0004-6361:20020684
18 pages, 13 figures, accepted for publication in Astronomy and Astrophysics
arxiv created 2002/05/14 · openalex publication_date 2002/07/01 · arxiv updated 2009/12/01 · openalex created_date 2022/10/04 · openalex updated_date 2026/07/31
An exact model for magnetized and rotating outflows, underpressured at their axis, is analysed by means of a nonlinear separation of the variables in the two-dimensional governing magnetohydrodynamic (MHD) equations for axisymmetric plasmas. The outflow starts subsonically and subAlfvénically from the central gravitating source and its surrounding accretion disk and after crossing the MHD critical points, high values of the Alfvén Mach number may be reached. Three broad types of solutions are found: (a) collimated jet-type outflows from efficient magnetic rotators where the outflow is confined by the magnetic hoop stress; (b) collimated outflows from inefficient magnetic rotators where the outflow is cylindrically confined by thermal pressure gradients; and (c) radially expanding wind-type outflows analogous to the solar wind. In most of the cases examined cylindrically collimated (jet-type) outflows are naturally emerging with thermal and magnetic effects competing in the acceleration and the confinement of the jet. The interplay of all MHD volumetric forces in accelerating and confining the jet is displayed along all its length and for several parameters. The solutions may be used for a physical understanding of astrophysical outflows, such as those associated with young stellar objects, planetary nebulae, extragalactic jets, etc.