Alpha loss-cone instability in the central cell of a tandem-mirror reactor

Thesis/Dissertation · Thu Jan 01 04:00:00 EST 1987

OSTI ID:6986141

Ho, S K

D-T fusion-born alpha particles are mirror-confined in the central cell of a tandem-mirror reactor. The resulting anisotropic loss-cone distribution of the alpha particles in velocity space is capable of destabilizing low-frequency plasma waves, thus affecting the energy balance in a tandem mirror plasma. The low-frequency waves of a cold, cylindrical, sharp-boundary, D-T plasma are studied. Techniques were developed to trace the wave-propagation regions and search the wave eigenfrequencies. Three branches of waves are found, namely the Alfven, hybrid, and fast waves; but only the Alfven wave is destabilized by the alpha loss-cone instability. The modeling of the alpha distribution function for the linear and quasi-linear instability calculations is done by a diffusion-front method and a numerical finite-difference method, respectively. The growth rate of the instability is basically determined by the alpha number density, the loss-cone angle, and the polarization of the wave. These quantities are in turn mainly affected by the density and temperature of the plasma ions and electrons, the mirror ratio, and the plasma radius. A stability boundary in the n-T plane is constructed to locate the stable and unstable regions. The instability is found to occur with moderate values of plasma density and temperatures.

• Research Organization: Illinois Univ., Urbana (USA)
• OSTI ID: 6986141
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700107* -- Fusion Energy-- Plasma Research-- Instabilities
700108 -- Fusion Energy-- Plasma Research-- Wave Phenomena
ALPHA PARTICLES
CHARGED PARTICLES
D-T REACTORS
DISTRIBUTION FUNCTIONS
EIGENFREQUENCY
ELECTROMAGNETIC RADIATION
ENERGY BALANCE
FUNCTIONS
INSTABILITY
INSTABILITY GROWTH RATES
LONG WAVE RADIATION
LOSS CONE INSTABILITY
MAGNETIC MIRROR TYPE REACTORS
PLASMA INSTABILITY
PLASMA MICROINSTABILITIES
PLASMA WAVES
RADIATIONS
RADIOWAVE RADIATION
THERMONUCLEAR REACTORS
TMR REACTORS