Microwave Emission from a Nonrelativistic Electron Beam.
Abstract
Testing was conducted at the Physics International MBS Facility during the time periods of 9-20 July and 4-7 September to investigate the interaction between an ambient plasma and a simulated photoelectron boundary layer. During the test period, 241 shots were taken on the electron-beam generator, resulting in approximately 1,500 data recordings. The primary purpose of the test program was to measure the microwave energy emitted by the electron distribution both with and without the presence of an ambient plasma. A microwave spectrometer covering the frequency range 1.12 to 18 GHz was used. Broadband microwave radiation was observed in the absence of an ambient plasma, presumably due to virtual cathode phenomena or reflexing of the emitted electrons. The peak energy of the electron beam was about 140 keV, and the average current density was in the range of 1 to 7 A/sq. cm over 730 sq. cm. This translates to an average electron density of approximately 10 to the 8th power to 10 to the 9th power per cubic centimeter. Both discrete and broadband microwave radiation were observed with an ambient plasma of density 10 to the 8th power to 10 to the 10th power electrons/cu cm. Efficiency for the conversion of electron energy to microwave energy is in the range of 0.05 to 0.3 percent. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 31, 1984
- Accession Number
- ADA166159
Entities
People
- E. Cozart
- S. Face
- T. Tumolillo
- W. Hobbs
Organizations
- Kaman Corporation