skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Energetic Particle-induced Geodesic Acoustic Mode

Abstract

A new energetic particle-induced Geodesic Acoustic Mode (EGAM) is shown to exist. The mode frequency, mode structure, and mode destabilization are determined non-perturbatively 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 for high energetic particle pressure and large safety factor. These results are consistent with the recent experimental observation of the beam- driven n=0 mode in DIII-D. The new mode is important since it can degrade energetic particle confinement as shown in the DIII-D experiments. The new mode may also affect the thermal plasma confinement via its interaction with plasma micro-turbulence.

Authors:
Publication Date:
Research Org.:
Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
938974
Report Number(s):
PPPL-4347
TRN: US0806763
DOE Contract Number:  
DE-ACO2-76CHO3073
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ACOUSTICS; CONFINEMENT; DOUBLET-3 DEVICE; GEODESICS; KINETICS; PLASMA; PLASMA CONFINEMENT; SAFETY; Tokamaks; Wave Interaction, Particles; Oscillations; Low Frequency

Citation Formats

Fu, G Y. Energetic Particle-induced Geodesic Acoustic Mode. United States: N. p., 2008. Web. doi:10.2172/938974.
Fu, G Y. Energetic Particle-induced Geodesic Acoustic Mode. United States. https://doi.org/10.2172/938974
Fu, G Y. 2008. "Energetic Particle-induced Geodesic Acoustic Mode". United States. https://doi.org/10.2172/938974. https://www.osti.gov/servlets/purl/938974.
@article{osti_938974,
title = {Energetic Particle-induced Geodesic Acoustic Mode},
author = {Fu, G Y},
abstractNote = {A new energetic particle-induced Geodesic Acoustic Mode (EGAM) is shown to exist. The mode frequency, mode structure, and mode destabilization are determined non-perturbatively 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 for high energetic particle pressure and large safety factor. These results are consistent with the recent experimental observation of the beam- driven n=0 mode in DIII-D. The new mode is important since it can degrade energetic particle confinement as shown in the DIII-D experiments. The new mode may also affect the thermal plasma confinement via its interaction with plasma micro-turbulence.},
doi = {10.2172/938974},
url = {https://www.osti.gov/biblio/938974}, journal = {},
number = ,
volume = ,
place = {United States},
year = {2008},
month = {9}
}