非Maxwell电子速度分布对受激散射的影响

从考虑动理学效应的受激散射不稳定性的线性理论出发,对于n=2的Maxwell分布函数直到n=5的饱和情况的超高斯分布函数,计算了电子等离子体波和离子声波的频率和阻尼率。对受激喇曼散射和受激布里渊散射进行分析,结果表明,在激光高Z等离子体中,或者在具有激光热斑的中等Z等离子体中,电子等离子体波的阻尼率降低很多,离子声波的频率比Maxwell分布情况升高约15%。这些结果可和实验进行比较。

EFFECTS OF NON-MAXWELLIAN ELECTRON VELOCITY DISTRIBUTION ON STIMULATED SCATTERING

According to the linear theory of stimulated scattering instabilities taking into count kinetic effects, the frequencies and the damping rates of an electron plasma wave (PEW) and of an ion-acoustic wave (IAW) are computed in a maxwellian electron velocity distribution function(n=2) to the non-Maxwellian saturated (n=5) limit. Stimulated Raman scattering and stimulated Brillouin scattering are analyzed, the results show that in high-Z plasmas or in laser hot spots with moderate Z, the damping rate of an electron plasma wave is substantially lower and the frequency of an ion-acoustic wave significantly higher than those in a Maxwellian distribution, and its damping rate is also lower.