Compact Millimeter Wave Cyclotron Resonance Maser.
Abstract
The experimental efforts have focussed on building the gyrotron chamber and associated apparatus. The system is now operational and measurements have begun. The results have been extremely encouraging. Using only 50 kW of the 200 kW available from our X-band magnetron, the rf accelerator has produced 100 mA, 100-250 keV beams. Millimeter wave measurements have been made. Our second gyrotron cavity, which was designed to be exited by approximately 150 keV beams, has yielded approximately 100 W at 26-46 GHz (3rd-6th cyclotron harmonics), corresponding to 1% electron to output wave energy conversion efficiency. This cavity was designed to be undercoupled due to start-oscillation considerations. Therefore, the efficiency of electron energy into cavity wave power was on order of 5%. The next cavity to be tested is critically coupled for higher power operation. Our theoretical activities include a theoretical description of the large-orbit cylcotron harmonic maser which yields encouraging values for device efficiency. Efficiencies as high as 8% have been predicted at millimeter-wavelength operation with a uniform magnetic field. By properly tapering the magnetic field so that the gyrofrequency remains approximately constant as the electrons lose energy this may be increased to 16%. In addition, a small-signal theory of the harmonic gyrotron has been developed which yields the value of beam current necessary for oscillation.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1982
- Accession Number
- ADA120318
Entities
People
- D. B. Mcdermott
- N. C. Luhmann Jr.
- W. A. Peebles
Organizations
- University of California, Los Angeles