Characteristics of Plasma Produced by Thermionic Cathodes with Radial Electric Fields,
Abstract
The report describes a preliminary survey of the steady-state characteristics of four plasma sources developed for a mirror machine experiment. All the sources included thermionic spiral cathodes to produce radial electric fields in the plasma. The sources tested were: (a) radial arc, (b) axial arc, (c) interdigital Lisitano coil with cathode and (d) helical Lisitano coil with cathode. Distributions of electron temperature, ion density, and floating potential, together with local measurements of rms noise level and dominant oscillation frequencies, are presented. Plasma parameters were in the following ranges; electron temperature 10,000 - 80,000 K and ion density 10 to the power of 9 to 10 to the power of 13/cc. Typically the floating potential varied parabolically with radius in the region influenced by the cathode. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1972
- Accession Number
- AD0754233
Entities
People
- John S. Martin
- Merrill L. Andrews
Organizations
- Wright State University