Theory of phase-locked gyrotrons operating at cyclotron harmonics

Author

Latham, P.E. ; Levush, B. ; Nusinovich, G.S. ; Parikh, S.

Author_Institution

Inst. for Plasma Res., Maryland Univ., College Park, MD, USA

Volume

22

Issue

5

fYear

1994

fDate

10/1/1994 12:00:00 AM

Firstpage

818

Lastpage

824

Abstract

The theory of phase-locked gyrotrons operating at cyclotron harmonics is developed, with particular attention given to the effects of electron velocity spread. Extensive studies are made for operation at the second harmonic in which phase locking is achieved by subharmonic prebunching. One result of these studies is that we are able to predict, for a range of velocity spreads, the parameters that yield the highest efficiency. More important, we find that for electron beams with velocity spread and a finite transit angle in the drift region, the bandwidth of stable operation is drastically reduced. This effect can be mitigated by properly tapering the external magnetic field there. Such tapering is necessary in devices where the bandwidth is required to be a reasonable fraction of 1/Q

Keywords

gyrotrons; harmonics; microwave generation; microwave oscillators; phase locked oscillators; cyclotron harmonics; drift region; electron velocity spread; external magnetic field tapering; finite transit angle; phase-locked gyrotrons; second harmonic; subharmonic prebunching; Bandwidth; Cyclotrons; Electromagnetic radiation; Electron beams; Frequency; Gyrotrons; Klystrons; Magnetic fields; Phase control; Resonance;

fLanguage

English

Journal_Title

Plasma Science, IEEE Transactions on

Publisher

ieee

ISSN

0093-3813

Type

jour

DOI

10.1109/27.338297

Filename

338297