Relaxation of a fast ion beam in a tokamak plasma

Journal Article · Sat Jul 01 04:00:00 EDT 1978 · Sov. J. Plasma Phys. (Engl. Transl.); (United States)

OSTI ID:6197582

Bardakov, V M

The quasilinear relaxation of a fast ion beam due to unstable Alfven waves is analyzed in connection with the problem of a two-component tokamak. Quasilinear relaxation is incorporated in a calculation of the thermonuclear efficiency (Q) of a two-component--tokamak fusion reactor. If the quasilinear relaxation is assumed to occur instantaneously, the thermonuclear Q is lower than the classical value, calculated for purely Coulomb relaxation of the beam, by an average factor of five. Magnetic shear causes a nearly instantaneous quasilinear relaxation by stable Alfven noise in the absence of shear) to convert into a slow diffusive spreading of the beam distribution function. This spreading comes to a halt in a time comparable to the characteristic Coulomb time. The local value of Q falls off significantly in this case only near the center of the plasma column, where the shear is small. Q averaged over the column, on the other hand, decreases by only a few percent from the classical value if the beam density does not have a maximum at the center of the plasma column.

• Research Organization: Institute of Geomagnetism, the Ionosphere, and Radio-Wave Propagation, Siberian Branch, Academy of Sciences of the USSR, Irkutsk
• OSTI ID: 6197582
• Journal Information: Sov. J. Plasma Phys. (Engl. Transl.); (United States), Journal Name: Sov. J. Plasma Phys. (Engl. Transl.); (United States) Vol. 4:4; ISSN SJPPD
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700101 -- Fusion Energy-- Plasma Research-- Confinement
Heating
& Production
700105* -- Fusion Energy-- Plasma Research-- Plasma Kinetics-Theoretical-- (-1987)
ALFVEN WAVES
BEAM INJECTION
BEAM-PLASMA SYSTEMS
BEAMS
CLOSED PLASMA DEVICES
DATA
DATA FORMS
EFFICIENCY
ELECTRONS
ELEMENTARY PARTICLES
FERMIONS
HYDROMAGNETIC WAVES
INFORMATION
INSTABILITY
ION BEAMS
ISOLATED VALUES
LEPTONS
NEUTRAL ATOM BEAM INJECTION
NUMERICAL DATA
PLASMA INSTABILITY
PLASMA MICROINSTABILITIES
QUASILINEAR PROBLEMS
RELAXATION
SHEAR
THEORETICAL DATA
THERMONUCLEAR DEVICES
THERMONUCLEAR REACTORS
TOKAMAK DEVICES
TRAPPED ELECTRONS
TWO-COMPONENT TORUS