Cho Jungyeon, Lazarian A
Astronomy Department, University of Wisconsin, Madison, WI 53706, USA.
Phys Rev Lett. 2002 Jun 17;88(24):245001. doi: 10.1103/PhysRevLett.88.245001. Epub 2002 May 31.
We present a model for compressible sub-Alfvénic isothermal magnetohydrodynamic (MHD) turbulence in low- beta plasmas and numerically test it. We separate MHD fluctuations into three distinct families: Alfvén, slow, and fast modes. We find that production of slow and fast modes by Alfvénic turbulence is suppressed. As a result, Alfvén modes in compressible regime exhibit scalings and anisotropy similar to those in incompressible regime. Slow modes passively mimic Alfvén modes. However, fast modes show isotropy and a scaling similar to acoustic turbulence.
我们提出了一个适用于低β等离子体中可压缩亚阿尔文等温磁流体动力学（MHD）湍流的模型，并对其进行了数值测试。我们将MHD涨落分为三个不同的族：阿尔文模、慢模和快模。我们发现阿尔文湍流对慢模和快模的产生有抑制作用。因此，可压缩 regime 中的阿尔文模表现出与不可压缩 regime 中相似的标度律和各向异性。慢模被动地模仿阿尔文模。然而，快模表现出各向同性和与声湍流相似的标度律。
