{beta} suppression of Alfven cascade modes in the National Spherical Torus Experiment

Journal Article · Mon Oct 15 00:00:00 EDT 2007 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.2768038· OSTI ID:21057452

Fredrickson, E D; Gorelenkov, N N; Menard, J E; Bell, R E ^[1]; Crocker, N A; Kubota, S ^[2]; Heidbrink, W W ^[3]; Levinton, F M; Yuh, H ^[4]

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1. Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)
2. University of California, Los Angeles, California 90095 (United States)
3. University of California, Irvine, California 92697 (United States)
4. Nova Photonics, Princeton, New Jersey 08543 (United States)

Alfven cascade modes have been found in low density, low {beta} plasmas on the National Spherical Torus Experiment [M. Ono et al., Nucl. Fusion 40, 557 (2000)]. An extension of the theory of cascade modes which includes the coupling to geodesic acoustic modes [Breizman et al., Phys. Plasmas 12, 112506 (2005)] is shown to imply their absence for typical spherical tokamak ratios of electron thermal to magnetic energy, {beta}. A scan in electron {beta} confirmed a threshold for suppression of cascade modes in good agreement with theoretical predictions.

• OSTI ID: 21057452
• Journal Information: Physics of Plasmas, Vol. 14, Issue 10; Other Information: DOI: 10.1063/1.2768038; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ALFVEN WAVES
ELECTRONS
PLASMA
PLASMA CONFINEMENT
PLASMA DENSITY
SPHERICAL CONFIGURATION
TOKAMAK DEVICES