Effect on Landau damping rates for a non-Maxwellian distribution function consisting of two electron populations  

作　　者：M.N.S.Qureshi S.Sehar H.A.Shah J.B.Cao 

机构地区：[1]Space Science Institute,Beihang University [2]Department of Physics,Government College University

出　　处：《Chinese Physics B》2013年第3期358-365,共8页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China (Grant No. 40931054);the National Basic Research Program of China (Grant No. 2011CB811404);the Higher Education Commission of China (Grant No. 20-1886/R&D/10)

摘　　要：In many physical situations where a laser or electron beam passes through a dense plasma,hot low-density electron populations can be generated,resulting in a particle distribution function consisting of a dense cold population and a small hot population.Presence of such low-density electron distributions can alter the wave damping rate.A kinetic model is employed to study the Landau damping of Langmuir waves when a small hot electron population is present in the dense cold electron population with non-Maxwellian distribution functions.Departure of plasma from Maxwellian distributions significantly alters the damping rates as compared to the Maxwellian plasma.Strong damping is found for highly nonMaxwellian distributions as well as plasmas with a higher density and hot electron population.Existence of weak damping is also established when the distribution contains broadened flat tops at the low energies or tends to be Maxwellian.These results may be applied in both experimental and space physics regimes.In many physical situations where a laser or electron beam passes through a dense plasma,hot low-density electron populations can be generated,resulting in a particle distribution function consisting of a dense cold population and a small hot population.Presence of such low-density electron distributions can alter the wave damping rate.A kinetic model is employed to study the Landau damping of Langmuir waves when a small hot electron population is present in the dense cold electron population with non-Maxwellian distribution functions.Departure of plasma from Maxwellian distributions significantly alters the damping rates as compared to the Maxwellian plasma.Strong damping is found for highly nonMaxwellian distributions as well as plasmas with a higher density and hot electron population.Existence of weak damping is also established when the distribution contains broadened flat tops at the low energies or tends to be Maxwellian.These results may be applied in both experimental and space physics regimes.

关 键 词：Landau damping Langmuir waves two electron populations non-Maxwellian distribution function 

分 类 号：O53[理学—等离子体物理]