Critical Initial Amplitude of Langmuir Wave Damping  

作　　者：徐慧 盛政明 

机构地区：[1]Shandong Provincial Key Laboratory of Laser Polarization and Information Technology,Department of Physics,Qufu Normal University [2]Key Laboratory for Laser Plasmas(Ministry of Education) and Department of Physics,Shanghai Jiaotong University [3]Beijing National Laboratory for Condensed Matters,Institute of Physics,Chinese Academy of Sciences

出　　处：《Plasma Science and Technology》2012年第3期181-186,共6页等离子体科学和技术（英文版）

基　　金：supported by National Natural Science Foundation of China (Nos.11147025, 10947108, 11075105);the National Basic Research Program of China (No.2009GB105002);the Natural Science Foundation of Shandong Province of China (No.Q2008A05);the Foundation of Qufu Normal University of China (No.BSQD09011)

摘　　要：By one-dimensional Vlasov-Poisson simulation, the critical initial state marking the transition between the Landau scenario, in which the electric fields definitively damped to zero and the O＇NEIL scenario, in which the Landau damping is stopped after a certain damping stage, is studied. It is found that the critical initial amplitude e＊ can only exist when the product of the wave number （k~） and the electron thermal velocity （vth） is moderate, that is, 0.2 〈 k^vth 〈 0.7. Otherwise, no critical initial amplitude is found. The value c＊ increases with the increase in km for a fixed Vth, and also increases with the increase in Vth for a fixed kin. When kmVth is fixed, the value s＊ also changes with the wave number and the electron thermal velocity, even though the damping rate and the oscillation frequency are the same in this case.By one-dimensional Vlasov-Poisson simulation, the critical initial state marking the transition between the Landau scenario, in which the electric fields definitively damped to zero and the O＇NEIL scenario, in which the Landau damping is stopped after a certain damping stage, is studied. It is found that the critical initial amplitude e＊ can only exist when the product of the wave number （k~） and the electron thermal velocity （vth） is moderate, that is, 0.2 〈 k^vth 〈 0.7. Otherwise, no critical initial amplitude is found. The value c＊ increases with the increase in km for a fixed Vth, and also increases with the increase in Vth for a fixed kin. When kmVth is fixed, the value s＊ also changes with the wave number and the electron thermal velocity, even though the damping rate and the oscillation frequency are the same in this case.

关 键 词：Landau damping critical initial amplitude Vlasov-Poisson simulation 

分 类 号：O534[理学—等离子体物理]