Gary S Peter
Space Science Institute, Boulder, CO, USA
Philos Trans A Math Phys Eng Sci. 2015 May 13;373(2041). doi: 10.1098/rsta.2014.0149.
Plasma turbulence consists of an ensemble of enhanced, broadband electromagnetic fluctuations, typically driven by multi-wave interactions which transfer energy in wavevector space via non- linear cascade processes. Temperature anisotropy instabilities in collisionless plasmas are driven by quasi-linear wave-particle interactions which transfer particle kinetic energy to field fluctuation energy; the resulting enhanced fluctuations are typically narrowband in wavevector magnitude and direction. Whatever their sources, short-wavelength fluctuations are those at which charged particle kinetic, that is, velocity-space, properties are important; these are generally wavelengths of the order of or shorter than the ion inertial length or the thermal ion gyroradius. The purpose of this review is to summarize and interpret recent computational results concerning short-wavelength plasma turbulence, short-wavelength temperature anisotropy instabilities and relationships between the two phenomena.
等离子体湍流由增强的宽带电磁涨落组成,通常由多波相互作用驱动,这些相互作用通过非线性级联过程在波矢空间中传递能量。无碰撞等离子体中的温度各向异性不稳定性由准线性波粒相互作用驱动,这种相互作用将粒子动能转化为场涨落能量;由此产生的增强涨落在波矢大小和方向上通常是窄带的。无论其来源如何,短波长涨落是指带电粒子动力学(即速度空间)特性起重要作用的涨落;这些通常是与离子惯性长度或热离子回旋半径量级相当或更短的波长。本综述的目的是总结和解释关于短波长等离子体湍流、短波长温度各向异性不稳定性以及这两种现象之间关系的近期计算结果。