Electromagnetic wave scattering from magnetic fluctuations in tokamaks

Journal Article · Sun Mar 01 04:00:00 EST 1992 · Physics of Fluids B; (United States)

DOI:https://doi.org/10.1063/1.860259· OSTI ID:7205647

Vahala, L ^[1]; Vahala, G ^[2]; Bretz, N ^[3]

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1. Department of Electrical and Computer Engineering, Old Dominion University, Norfolk, Virginia 23529 (United States)
2. Department of Physics, College of William and Mary, Williamsburg, Virginia 23185 (United States)
3. Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08544 (United States)

Cross sections are calculated for electromagnetic wave scattering and mode transformation from magnetic and density fluctuations in a homogeneous plasma. For the special case of scattering perpendicular to the magnetic field, density fluctuations scatter ordinary to ordinary and extraordinary to extraordinary modes---but cannot transform these modes. On the other hand, magnetic fluctuations perpendicular to the field can transform modes but cannot scatter on a single branch. For incident frequencies on the order of the electron plasma frequency or gyrofrequency, the cross sections for scattering and transformation due to field and density fluctuations have a similar value. Estimates are given for scattering in a tokamak plasma with special emphasis on the question of how to detect and localize magnetic field fluctuations. Ray tracing calculations, estimates of practical limitations on polarization technique, and lower bound estimates on density and magnetic fluctuation levels show that magnetic fluctuations can be detected and localized by this method.

• DOE Contract Number: FG05-90ER54093; FG05-84ER53176; AC02-76CH03073
• OSTI ID: 7205647
• Journal Information: Physics of Fluids B; (United States), Journal Name: Physics of Fluids B; (United States) Vol. 4:3; ISSN 0899-8221; ISSN PFBPE
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700340* -- Plasma Waves
Oscillations
& Instabilities-- (1992-)
CLOSED PLASMA DEVICES
CROSS SECTIONS
DISPERSION RELATIONS
ELECTROMAGNETIC FIELDS
ELECTROMAGNETIC RADIATION
ELECTRON DENSITY
ELECTRON DRIFT
FLUCTUATIONS
FLUID MECHANICS
GYROFREQUENCY
HYDRODYNAMICS
MAGNETIC FIELDS
MAGNETOHYDRODYNAMICS
MECHANICS
MICROWAVE RADIATION
POLARIZATION
RADIATIONS
SCATTERING
THERMONUCLEAR DEVICES
TOKAMAK DEVICES
VARIATIONS
WAVE PROPAGATION