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采用考虑粒子温度各向异性热等离子体介电张量模型, 借助磁化、均匀密度分布等离子体中电磁波的一般色散关系, 在低磁场、低气压螺旋波等离子体典型参量条件下, 理论分析了电子温度各向异性对电磁模式传播特性和角向对称模功率沉积的影响. 研究结果表明: 对于给定的纵向静磁场 B 0(或波频率 ω), 存在一个临界波频率 ω cr(或纵向静磁场 B 0,cr), 当 ω > ω cr(或 B 0< B 0,cr)时, 电子回旋谐波遭受的阻尼开始显著增大; 相比粒子温度各向同性情形, 粒子温度各向异性彻底改变了波的传播特性, 即相位常数和衰减常数均出现峰值现象; 在考虑电子有限拉莫尔半径效应和电子温度各向异性情形下, Trivelpiece-Gould (TG)波碰撞阻尼在整个电磁波功率沉积中占据主导地位, 电子纵向温度 T e,//存在某一临界值, 在此临界值处TG波功率沉积出现峰值 P abs,TG, 且随着 T e,⊥/ T e,//的减小, 此功率沉积峰值 P abs,TG逐渐增强.As the core issue in helicon discharge, the physical mechanism behind the high ionization rate phenomenon is still not fully understood. Based on the warm plasma dielectric tensor model which contains both the particle drift velocity and temperature anisotropy effect, by employing the general dispersion relation of electromagnetic waves propagating in magnetized and uniform plasma with typical helicon discharge parameter conditions, wave mode propagation characteristic and collisional, cyclotron and Landua damping induced wave power deposition properties of azimuthally symmetric mode are theoretically investigated. Systematic analysis shows the following findings. 1) Under typical helicon plasma parameter conditions, i.e. wave frequency ω/(2π)=13.56 MHz, ion temperature is one tenth of the electron temperature, and for a given magnetic field B 0(or wave frequency ω), there exists a critical wave frequency ω cr(or magnetic field B 0,cr), above which (or below B 0,cr) the damping of the n =1, 2, 3 cyclotron harmonics begins to increase sharply. 2) For the electron temperature isotropic case, the attenuation constants of different harmonics start to increase significantly and monotonically at different thresholds of magnetic field, while the phase constant abruptly increases monotonically from the beginning of the parameter interval. On the other hand, for the electron temperature anisotropic case, both the phase constant and attenuation constant have peaking phenomenon, i.e. the attenuation constant begins to increase sharply at a certain value of B 0and meanwhile the phase constant presents a maximum value near the same value of magnetic field, thus the phase constant starts to keep constant at a certain value of B 0and meanwhile the attenuation constant has a maximum value near this same value of magnetic field. 3) For the wave power deposition properties, under electron temperature anisotropy conditions, power deposition due to collisional damping of Trivelpiece-Gould (TG) wave plays a dominant role in a low field ( B 0= 48 Gs) (1 Gs = 10 –4T); by considering the electron finite Larmor radius (FLR) effect, the power deposition of TG wave presents a maximum value at a certain point of parallel electron temperature T e, //; with the decrease of T e,⊥/ T e, //, the maximum value of power deposition increases gradually. All these findings are very important in further revealing the physical mechanism behind the high ionization rate in helicon plasma.
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${\varPi _{su} }$ u= 1 u= 2 u= 3 s= 1 $ {{\text{J}}_m}({k_{ \bot m, {\text{H}}}}a) $ $ {{\text{J}}_m}({k_{ \bot m, {\text{TG}}}}a) $ $ - {\text{j}}{k_{ \bot m, v}}{\text{H}}_m^{(1)}({k_{ \bot m, v}}a) $ s= 2 $\begin{gathered} k_{ \bot m, {\text{TG} } }^2\left[ {m{k_{//, m} }{ {\text{J} }_m}({k_{ \bot m, {\text{H} } } }a) } \right. \\ \left. +{ {k_{\text{H} } }{k_{ \bot m, {\text{H} } } }a{ {\text{J} }_m'} ({k_{ \bot m, {\text{H} } } }a)} \right] \\ \end{gathered}$ $\begin{gathered} k_{ \bot m, {\text{H} } }^2\left[ {m{k_{//, m} }{ {\text{J} }_m}({k_{ \bot m, {\text{TG} } } }a) } \right. \\ \left. +{ {k_{\text{H} } }{k_{ \bot m, {\text{TG} } } }a{ {\text{J} }_m'} ({k_{ \bot m, {\text{TG} } } }a)} \right] \\ \end{gathered}$ $ {\text{j}}k_{ \bot m, {\text{H}}}^2 k_{ \bot m, {\text{TG}}}^2 m{\text{H}}_m^{(1)}({k_{ \bot m, v}}a) $ s= 3 $\begin{gathered} k_{ \bot m, {\text{TG} } }^2\left[ {m{k_{\text{H} } }{ {\text{J} }_m}({k_{ \bot m, {\text{H} } } }a) } \right. \\ \left. +{ {k_{//, m} }{k_{ \bot m, {\text{H} } } }a{ {\text{J} }_m'} ({k_{ \bot m, {\text{H} } } }a)} \right] \\ \end{gathered}$ $\begin{gathered} k_{ \bot m, {\text{H} } }^2\left[ {m{k_{ {\text{TG} } } }{ {\text{J} }_m}({k_{ \bot m, {\text{TG} } } }a) } \right. \\ \left. +{ {k_{//, m} }{k_{ \bot m, {\text{TG} } } }a{ {\text{J} }_m'} ({k_{ \bot m, {\text{TG} } } }a)} \right] \\ \end{gathered}$ ${\text{j} }k_{ \bot {m}, {\text{H} } }^2 k_{ \bot {m}, {\text{TG} } }^2 {k_{ \bot {m}, v} }a{\text{H}_m^{(1)' }}({k_{ \bot {m}, v} }a)$ 
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