Theoretical Studies of Drift-Alfven and Energetic-Particle Physics in Fusion Plasmas. (Report for June 1, 2002-November 30, 2004).

Chen, L.

Technical Information Center Oak Ridge Tennessee

关键词: Plasma diagnostics;    Alfven waves;    Drift instability;    Alpha particles;    Physics;   

RP-ID  :  DE2006838916

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

A theoretical model is proposed for the nonlinear saturation of high-m Alfven-ballooning instabilities in in magnetospheric plasmas. Here, m is the azimuthal wave number. In the present model, a broad spectrum of Alfven waves nonlinearly generate ion-sound density perturbations; which, in turn, scatter the Alfven turbulence toward lower frequencies. Balancing the linear instability growth rate with the nonlinear scattering (Landau damping) rate then yield the corresponding saturated spectrum, which tends to peak near the bottom of the eigenmode frequencies. The theory also gives estimates of wave amplitudes at saturation in reasonable agreement with satellite observations.