Beta-induced Alfvén-acoustic eigenmodes in National Spherical Torus Experiment and DIII-D driven by beam ions

Kinetic theory and experimental observations of a special class of energetic particle driven instabilities called here beta-induced Alfvén-acoustic eigenmodes (BAAEs) are reported confirming, previous results [ N. N. Gorelenkov , Plasma Phys. Controlled Fusion 49 , B371 ( 2007 ) ]. The kinetic theor...

Full description

Saved in:
Bibliographic Details
Published in:Physics of plasmas 2009-05, Vol.16 (5), p.056107-056107-9
Main Authors: Gorelenkov, N. N., Van Zeeland, M. A., Berk, H. L., Crocker, N. A., Darrow, D., Fredrickson, E., Fu, G.-Y., Heidbrink, W. W., Menard, J., Nazikian, R.
Format: Article
Language:English
Subjects:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY
DISPERSION RELATIONS
DOUBLET-3 DEVICE
EIGENFUNCTIONS
EIGENVALUES
IONS
PLASMA CONFINEMENT
PLASMA INSTABILITY
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Kinetic theory and experimental observations of a special class of energetic particle driven instabilities called here beta-induced Alfvén-acoustic eigenmodes (BAAEs) are reported confirming, previous results [ N. N. Gorelenkov , Plasma Phys. Controlled Fusion 49 , B371 ( 2007 ) ]. The kinetic theory is based on the ballooning dispersion relation where the drift frequency effects are retained. BAAE gaps are recovered in kinetic theory. It is shown that the observed certain low-frequency instabilities on DIII-D [ J. L. Luxon , Nucl. Fusion 42 , 614 ( 2002 ) ] and National Spherical Torus Experiment [ M. Ono , S. M. Kaye , Y.-K. M. Peng , Nucl. Fusion 40 , 557 ( 2000 ) ] are consistent with their identification as BAAEs. BAAEs deteriorate the fast ion confinement in DIII-D and can have a similar effect in next-step fusion plasmas, especially if excited together with multiple global toroidicity-induced shear Alfvén eigenmode instabilities. BAAEs can also be used to diagnose safety factor profiles, a technique known as magnetohydrodynamic spectroscopy.
ISSN:1070-664X
1089-7674
DOI:10.1063/1.3097920