论文标题
非平衡两流等离子体中集体汤姆森散射的离子声学特征
Ion-acoustic feature of collective Thomson scattering in non-equilibrium two-stream plasmas
论文作者
论文摘要
我们从理论和数字上研究了汤姆森散射（CTS）在两流等离子体中的离子声学特征。当电子分布在与离子声特征的两个谐振峰相对应的相速度下两个（固定和移动）组件的功能相互重叠时，理论光谱显示出不对称性，因为电子兰道湿度的速率在两个峰上是不同的。数值模拟的结果与理论光谱很好。我们还证明了两个流型不稳定性在离子声学特征中的影响。在不稳定性的存在下，模拟光谱显示出与重叠情况相反趋势的不对称性，这是由于不稳定性引起的电子分布函数的时间变化而导致的。我们的结果表明，两流等离子体对CTS光谱具有显着影响，并且在离子声学特征中可以观察到不稳定性引起的波。
We theoretically and numerically investigate the ion-acoustic features of collective Thomson scattering (CTS) in two-stream plasmas. When the electron distribution functions of two (stationary and moving) components overlap with each other at the phase velocities corresponding to the two resonant peaks of the ion-acoustic feature, the theoretical spectrum shows asymmetry because the rate of electron Landau damping is different for the two peaks. The results of numerical simulations agree well with the theoretical spectra. We also demonstrate the effect of a two-stream-type instability in the ion-acoustic feature. The simulated spectrum in the presence of the instability shows an asymmetry with the opposite trend to the overlapped case, which results from the temporal change of the electron distribution function caused by the instability. Our results show that two-stream plasmas have significant effects on CTS spectra and that the waves resulting from instabilities can be observed in the ion-acoustic feature.
