Electrostatic ion-cyclotron waves in a nonuniform magnetic field

Journal Article · Tue Oct 01 04:00:00 EDT 1985 · Phys. Fluids; (United States)

DOI:https://doi.org/10.1063/1.865348· OSTI ID:5366059

Cartier, S L; D'Angelo, N; Merlino, R L

The properties of electrostatic ion-cyclotron waves excited in a single-ended cesium Q machine with a nonuniform magnetic field are described. The electrostatic ion-cyclotron waves are generated in the usual manner by drawing an electron current to a small exciter disk immersed in the plasma column. The parallel and perpendicular (to B) wavelengths and phase velocities are determined by mapping out two-dimensional wave phase contours. The wave frequency f depends on the location of the exciter disk in the nonuniform magnetic field, and propagating waves are only observed in the region where f> or approx. =f/sub c/i, where f/sub c/i is the local ion-cyclotron frequency. The parallel phase velocity is in the direction of the electron drift. From measurements of the plasma properties along the axis, it is inferred that the electron drift velocity is not uniform along the entire current channel. The evidence suggests that the waves begin being excited at that axial position where the critical drift velocity is first exceeded, consistent with a current-driven excitation mechanism.

• Research Organization: Department of Physics and Astronomy, The University of Iowa, Iowa City, Iowa 52242
• OSTI ID: 5366059
• Journal Information: Phys. Fluids; (United States), Journal Name: Phys. Fluids; (United States) Vol. 28:10; ISSN PFLDA
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700108* -- Fusion Energy-- Plasma Research-- Wave Phenomena
ALKALI METALS
BREMSSTRAHLUNG
CESIUM
CYCLOTRON RADIATION
ELECTROMAGNETIC RADIATION
ELEMENTS
ENERGY-LEVEL TRANSITIONS
EXCITATION
FREQUENCY MEASUREMENT
ION WAVES
MAGNETIC FIELDS
METALS
OPEN PLASMA DEVICES
PLASMA
PLASMA WAVES
Q DEVICES
RADIATIONS
THERMONUCLEAR DEVICES