一种离子温度分布下的测地声模连续谱的参量激发

在离子温度为非均匀的等离子体中漂移波激发测地声模连续谱的过程中,对测地声模固有频率的径向分布函数的不均匀部分取双曲正切函数的情况,研究了漂移波边带模和测地声模连续谱的径向结构以及测地声模增长率.数值结果表明漂移波边带模的径向结构分布图都与简谐振荡都很接近,测地声模连续谱的能量都主要集中在参量激发的共振点附近,而测地声模增长率和泵波振幅的平方成正比.

Parametric Excitation of the Geodesic Acoustic Mode Continuum with a Model Profile of the Ion Temperature

The growth rate of the geodesic acoustic mode and the radial structures of the sideband drift waves and the geodesic acoustic modes continuum are studied as a parametric process in the tokamak plasmas with a non-uniform ion temperature profil for which the non-uniform part of the inherent geodesic acoustic mode frequency takes the form of tanh function.It is shown that the radial structures of the drift wave sideband are close to the harmonic function,the energies of the geodesic acoustic modes are mainly localized around the resonant points of the parametric excitations,and the growth rate is proportional to the square of the amplitude of the pump wave.