Accession Number : ADA293203

Title :   X-Band Magnicon Amplifier Research at the Naval Research Laboratory.

Descriptive Note : Interim rept.,

Corporate Author : NAVAL RESEARCH LAB WASHINGTON DC

Personal Author(s) : Gold, Steven H. ; Hafizi, Bahman ; Fliflet, Arne W.

PDF Url : ADA293203

Report Date : 19 APR 1995

Pagination or Media Count : 10

Abstract : We present a progress report on a program to develop a high-power second harmonic magnicon amplifier at 11.4 6Hz for linear accelerator applications. The experiments are being carried out on the NRL Long-Pulse Accelerator Facility using a plasma cathode to create the electron beam. Typical beam parameters are 500 kV, 200 A, 5.5 mm diameter, with a approximately 300 nsec voltage flattop and a approximately 10(exp -2) Hz repetition rate. An initial deflection cavity experiment demonstrated two-cavity gain of approximately 15dB at a frequency ship of 0.18%, in good agreement with theory and simulation. A complete five cavity magnicon circuit was designed via computer simulation, fabricated, and cold tested. This circuit is now undergoing experimental tests. In preliminary experiments, a low power saturation effect was observed in the deflection cavities, apparently due to plasma formation caused by the diode x-ray flux and by inadequate vacuum conditions. Following a major effort to improve the vacuum and surface conditions, very recent experiments have shown that is possible to "burn through" this low power saturation effect, and achieve high fields in the deflection cavities. However, high power emission from the output cavity has not yet been observed. We are also evaluating new fourth magnicon designs via time-dependent multimode simulations.

Descriptors :   *MICROWAVE AMPLIFIERS, COMPUTERIZED SIMULATION, DIODES, HIGH POWER, LOW POWER, EMISSION, TIME DEPENDENCE, SECOND HARMONIC GENERATION, EXPERIMENTAL DESIGN, FLUX(RATE), PLASMAS(PHYSICS), DEFLECTION, TEST METHODS, X RAYS, CATHODES, ELECTRON BEAMS, SURFACE PROPERTIES, MULTIMODE, X BAND, CAVITY RESONATORS, PLASMA ACCELERATORS.

Subject Categories : Electrical and Electronic Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE