Magnetic fields play an important role in astrophysical accretion discs and in the interstellar and intergalactic medium. They drive jets, suppress fragmentation in star-forming clouds and can have a significant impact on the accretion rate of stars. However, the exact amplification mechanisms of cosmic magnetic fields remain relatively poorly understood. Here, I start by reviewing recent advances in the numerical and theoretical modelling of the turbulent dynamo, which may explain the origin of galactic and intergalactic magnetic fields. While dynamo action was previously investigated in great detail for incompressible plasmas, I here place particular emphasis on highly compressible astrophysical plasmas, which are characterised by strong density fluctuations and shocks, such as the interstellar medium. I find that dynamo action works not only in subsonic plasmas, but also in highly supersonic, compressible plasmas, as well as for low and high magnetic Prandtl numbers. I further present new numerical simulations from which I determine the growth of the turbulent (un-ordered) magnetic field component ( B-turb) in the presence of weak and strong guide fields ( B-0). I vary B-0 over five orders of magnitude and find that the dependence of Bturb on B-0 is relatively weak, and can be explained with a simple theoretical model in which the turbulence provides the energy to amplify B-turb. Finally, I discuss some important implications of magnetic fields for the structure of accretion discs, the launching of jets and the star-formation rate of interstellar clouds.
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机译:用等离子体约束实现重力场的动态控制热核聚变(TLTS)方法,通过热辐射等离子体绝缘的壁反应堆防止中子辐射并节省磁场和等离子体的混合,使用旋转磁场的异步磁惯性约束反应堆(AMITYAR和HFM)为实施该方法,在该反应器中点燃热核反应的方法,爆炸式等离子发生器(VIP)的实施方法,以及具有HFM的特立普安瓿,以实现D + T反应和具有超高温热度的HFM D +3НЕ和1Н+11В的高温反应