Evidence of ‘two plasmon’ decay of energetic particle induced geodesic acoustic mode
نویسندگان
چکیده
Abstract Secondary low frequency mode generation by energetic particle induced geodesic acoustic (EGAM) observed in LHD experiment is studied using nonlinear gyrokinetic theory. It found that the EGAM can be significantly higher than local (GAM) collisionality plasmas, and it decay into two GAMs as its approaches twice GAM frequency, a process analogous to well-known plasmon instability. The condition for this occur also discussed.
منابع مشابه
Energetic-particle-induced geodesic acoustic mode.
A new energetic particle-induced geodesic acoustic mode (EGAM) is shown to exist. The mode frequency and mode structure are determined nonperturbatively by energetic particle kinetic effects. In particular the EGAM frequency is found to be substantially lower than the standard GAM frequency. The radial mode width is determined by the energetic particle drift orbit width and can be fairly large ...
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ژورنال
عنوان ژورنال: New Journal of Physics
سال: 2021
ISSN: ['1367-2630']
DOI: https://doi.org/10.1088/1367-2630/ac047a