论文标题
MHD湍流中Alfvén波的阻尼以及对宇宙射线流不稳定性和银河风的影响
Damping of Alfvén waves in MHD turbulence and implications for cosmic ray streaming instability and galactic winds
论文作者
论文摘要
MHD湍流潮湿的Alfvénic成分。从宇宙射线（CR）传播到星系和其他磁化系统中的流出和风，这种效果的后果对于许多过程都很重要。我们讨论了通过湍流和平面平行波的阻尼对流不稳定性阻尼的差异。前者发生在与CRS流的磁场的局部方向对齐的参考系统中。后者在平均磁场的参考框架中，传统上在血浆研究中考虑。我们还比较了流动不稳定性的湍流阻尼与离子中性碰撞阻尼，这成为在足够低电离分数下的主要阻尼效应。还讨论了数值测试和天体物理意义。
Alfvénic component of MHD turbulence damps Alfvénic waves. The consequences of this effect are important for many processes, from cosmic ray (CR) propagation to launching outflows and winds in galaxies and other magnetized systems. We discuss the differences in the damping of the streaming instability by turbulence and the damping of a plane parallel wave. The former takes place in the system of reference aligned with the local direction of magnetic field along which CRs stream. The latter is in the reference frame of the mean magnetic field and traditionally considered in plasma studies. We also compare the turbulent damping of streaming instability with ion-neutral collisional damping, which becomes the dominant damping effect at a sufficiently low ionization fraction. Numerical testing and astrophysical implications are also discussed.
