Collective scattering of CO/sub 2/-laser light from ion-acoustic turbulence

Journal Article · Sun Mar 01 04:00:00 EST 1981 · Phys. Fluids; (United States)

OSTI ID:6559922

Pots, B F.M.; Coumans, J J.H.; Schram, D C

The spectral density function S(k,..omega..) associated with spontaneous turbulence in a current-driven plasma of medium density (n/sub e/ = 10/sup 19/ to 10/sup 220/ m /sup -3/) is measured with the scattering of the radiation of a cw low-power CO/sub 2//sup -/ laser (P/sub i/ approx. = 2 W, lambda/sub i/ = 10.6 ..mu..m). Optical homodyne detection has been used. A remarkable result is that the level of fluctuations with wave vectors kparallelB is close to thermal; B is the magnetic field for plasma confinement. The level of fluctuations with kperpendicularB is several orders of magnitude larger than the thermal level. The phase velocity of these fluctuations is equal to the ion-acoustic velocity. A power law spectrum of the form n/sub e//n/sub e/ approx. ..omega../sup -2/ has been found. It is consistent with the spectrum below 1 MHz as measured by optical probes.

• Research Organization: Eindhoven University of Technology, The Netherlands
• OSTI ID: 6559922
• Journal Information: Phys. Fluids; (United States), Journal Name: Phys. Fluids; (United States) Vol. 24:3; ISSN PFLDA
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700102* -- Fusion Energy-- Plasma Research-- Diagnostics
CARBON DIOXIDE LASERS
CLOSED PLASMA DEVICES
DISPERSION RELATIONS
ELECTROMAGNETIC RADIATION
FLUCTUATIONS
FUNCTIONS
GAS LASERS
LASER RADIATION
LASERS
PLASMA DENSITY
PLASMA DIAGNOSTICS
RADIATIONS
SCATTERING
SPECTRAL DENSITY
SPECTRAL FUNCTIONS
THERMONUCLEAR DEVICES
TOKAMAK DEVICES
TURBULENCE
VARIATIONS