Search for lower-hybrid-drift fluctuations in a field-reversed configuration using CO/sub 2/ heterodyne scattering

Journal Article · Fri May 01 04:00:00 EDT 1987 · Phys. Fluids; (United States)

OSTI ID:6896580

Carlson, A W

An upper bound of (n-italic-tilde/sub e//n/sub e/) <10/sup -4/ for frequencies and wavenumbers relevant to the lower-hybrid-drift (LHD) instability is set on fluctuations in field-reversed configurations (FRC's) produced by TRX-2 (Fusion Techn. 9, 48 (1986)). LHD is a well-studied microinstability that is often invoked to explain particle loss rates in FRC's. The conventional technique of CO/sub 2/ laser scattering with heterodyne detection is here modified to compensate for severe refraction. The calibration of the system is verified by scattering from acoustic waves in salt. The measured bound is two orders of magnitude below both the fluctuation level usually predicted and the level needed to account for observed particle loss rates. Electron collisionality is identified as the most likely LHD stabilization mechanism. Some alternative explanations of anomalous loss rates are discussed.

• Research Organization: University of Washington, Seattle, Washington 98195 and Spectra Technology, Inc., Bellevue, Washington 98004
• OSTI ID: 6896580
• Journal Information: Phys. Fluids; (United States), Journal Name: Phys. Fluids; (United States) Vol. 30:5; ISSN PFLDA
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700102 -- Fusion Energy-- Plasma Research-- Diagnostics
700107* -- Fusion Energy-- Plasma Research-- Instabilities
CARBON DIOXIDE LASERS
DRIFT INSTABILITY
ELECTROMAGNETIC RADIATION
FLUID MECHANICS
GAS LASERS
HYDRODYNAMICS
INSTABILITY
LASER RADIATION
LASERS
MAGNETIC FIELD CONFIGURATIONS
MAGNETIC FIELD REVERSAL
MAGNETOHYDRODYNAMICS
MECHANICS
PLASMA
PLASMA DIAGNOSTICS
PLASMA INSTABILITY
PLASMA MICROINSTABILITIES
RADIATIONS
SCATTERING