Nonlinear interactions of focused resonance cone fields with plasmas

Journal Article · Sat Jan 01 04:00:00 EST 1977 · Phys. Fluids; (United States)

DOI:https://doi.org/10.1063/1.861698· OSTI ID:7327678

Stenzel, R L; Gekelman, W

A simple yet novel rf exciter structure has been developed for generating remotely intense rf fields in a magnetoplasma. It is a circular line source of radius R in a plane perpendicularB/sub 0/ driven with an rf signal at ..omega.. <..omega../sub c/approx. =..omega../sub p/ (where ..omega../sub c/, ..omega../sub p/ are the electron cyclotron and electron plasma frequency, respectively) which excites two resonance cones with focal points at z= +- R cotTHETA/sub c/ (THETA/sub c/ is the cone angle). The rf intensity increases away from the exciter to reach a maximum (approximately 20 dB enhancement) at the remote focal points. This arrangement is ideally suited to study nonlinear interactions free of boundary effects. At large applied rf signals, epsilon/sub 0/E/sub rf//sup 2//nkT/sub e/>0.2, a strong density depression in the focal region (deltan/n>40%) is observed. The density perturbation modifies the cone angle and field distribution. This nonlinear interaction leads to a rapid growth of ion acoustic wave turbulence and a corresponding random rf field distribution in a broadened focal region. The development of the interaction is mapped in space and time. (AIP)

• Research Organization: Department of Physics, University of California, Los Angeles, California 90024
• OSTI ID: 7327678
• Journal Information: Phys. Fluids; (United States), Journal Name: Phys. Fluids; (United States) Vol. 20:1; ISSN PFLDA
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700101* -- Fusion Energy-- Plasma Research-- Confinement
Heating
&amp; Production
ANTENNAS
ELECTRICAL EQUIPMENT
EQUIPMENT
FOCUSING
HEATING
HIGH-FREQUENCY HEATING
NONLINEAR PROBLEMS
PLASMA DENSITY
PLASMA HEATING
RF SYSTEMS
SPACE VEHICLES