Gyrotron Gun Study Report,
Abstract
The purpose of the program was to explore new gyrotron gun configurations and to design a low velocity spread replacement gun for the NRL 35 GHz gyro-TWT. The specific beam forming techniques which were studied were magnetic field reversal, transverse magnetic field kicker, and single anode (diode-like) Magnetron Injection Guns (MIGs). This report contains a summary of our work in each of these areas as well as a description of the new MIG design for the gyro-TWT. Gyrotron oscillators and amplifiers require an entirely different type of electron gun design than those normally used in conventional tube designs. The ideal beam must not only have the proper geometry to maximize the rf interaction with the selected waveguide circuit mode, but also, for maximum efficiency, there are two additional requirements: (1) the transverse velocity of the electrons must exceed the longitudinal velocity by a typical factor of 1.5 to 2 (intermixed helical electron trajectories are allowed); and (2) the spread in the longitudinal velocities must be small (on the order of 10-20% for oscillators, 2-5% for amplifiers). Several methods for producing gyrotron beams have been investigated, and most likely different approaches will be necessary for differing power levels and velocity spread requirements.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 18, 1981
- Accession Number
- ADA119707
Entities
People
- Anthony C. Attard
- J. Mark Baird