Dipartimento di Fisica and CNISM, Universitá di Pisa, 56127 Pisa, Italy.
Phys Rev Lett. 2010 May 21;104(20):205002. doi: 10.1103/PhysRevLett.104.205002. Epub 2010 May 17.
We present the first 2D hybrid-Vlasov simulations of turbulence in the solar wind that describe the evolution of the energy spectra in a range of two decades of wavelengths around the ion inertial scale. Several previous magnetohydrodynamics and particle-in-cell simulations in the range of large (fluid) wavelengths showed a marked anisotropy of the energy spectra in the direction perpendicular to the mean magnetic field. Here we give evidence that the parallel direction can also be a privileged way for turbulence to develop towards short scales, where kinetic effects govern the plasma dynamics.
我们呈现了首例二维混合 Vlasov 模拟太阳风中的湍流，描述了在离子惯性尺度周围两个数量级的波长范围内能量谱的演化。之前在大（流体）波长范围内的一些磁流体力学和粒子模拟显示，在垂直于平均磁场的方向上，能量谱具有明显的各向异性。在这里，我们证明平行方向也可以是湍流向短尺度发展的有利途径，在那里，动力学效应控制着等离子体动力学。
