An experimental study of current-driven electrostatic ion-cyclotron waves in a two-ion component of plasma

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1989

OSTI ID:6054725

Suszcynsky, D M

Two-ion component electrostatic ion-cyclotron (EIC) waves are studied in a single-ended Q-machine containing variable concentrations of Cs{sup +} and K{sup +} ions. Measurements of the excitation and propagation characteristics of the waves are presented and compared with available theories. The waves are internally excited by drawing an electron current along the magnetic field to an 11 mm diameter exciter disk. The relative ion concentrations are measured with a magnetic mass spectrometer which was designed and constructed to separate ions of different mass according t the size of their Larmor radii. Several EIC wave features are found to depend on the relative ion concentrations. Both Cs{sup +} and K{sup +} EIC waves can be simultaneously excited over a large range of ion concentrations. As the light ion (K{sup +}) concentration is increased, the frequency of the heavy ion (Cs{sup +}) mode shifts towards its cyclotron frequency. Likewise, the frequency of the light ion mode approaches the light ion-cyclotron frequency as the heavy ion concentration is increased. The critical drift velocity for the excitation of the heavy ion (Cs{sup +}) mode is more strongly dependent on the relative ion concentrations than that of the light ion (K{sup +}) mode. These results are of interest in the context of EIC wave excitation in the ionosphere.

• Research Organization: Iowa Univ., Iowa City, IA (USA)
• OSTI ID: 6054725
• Country of Publication: United States
• Language: English

Related Subjects

640201* -- Atmospheric Physics-- Auroral
Ionospheric
& Magetospheric Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CATIONS
CESIUM IONS
CHARGED PARTICLES
CRITICAL VELOCITY
CYCLOTRON FREQUENCY
EARTH ATMOSPHERE
ENERGY-LEVEL TRANSITIONS
EXCITATION
IONIC COMPOSITION
IONOSPHERE
IONS
MASS SPECTROMETERS
MEASURING INSTRUMENTS
PLANETARY IONOSPHERES
PLASMA WAVES
POTASSIUM IONS
QUANTITY RATIO
SPECTROMETERS
VELOCITY
WAVE PROPAGATION