[Table of Contents]

Plasma and Fusion Research

Volume 5, S1047 (2010)

Regular Articles


Numerical Analysis of Slow-Wave Instabilities in an Oversized Sinusoidally Corrugated Waveguide Driven by a Finitely Thick Annular Electron Beam
Kosuke OTUBO, Kazuo OGURA, Mitsuhisa YAMAKAWA and Yusuke TAKASHIMA
Graduate School of Science and Technology, Niigata University, 950-2181, Japan
(Received 8 January 2009 / Accepted 22 July 2009 / Published 26 March 2010)

Abstract

Three kinds of models are used for beam instability analyses: those based on a solid beam, an infinitesimally thin annular beam, and a finitely thick annular beam. In high-power experiments, the electron beam is an annulus of finite thickness. In this paper, a numerical code for a sinusoidally corrugated waveguide with a finitely thick annular beam is presented and compared with other models. Our analysis is based on a new version of the self-consistent linear theory that takes into account three-dimensional beam perturbations. Slow-wave instabilities in a K-band oversized sinusoidally corrugated waveguide are analyzed. The dependence of the Cherenkov and slow cyclotron instabilities on the annular thickness and guiding magnetic field are examined.


Keywords

annular beam, oversized sinusoidally corrugated waveguide, boundary condition, Cherenkov instability, slow cyclotron instability

DOI: 10.1585/pfr.5.S1047


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This paper may be cited as follows:

Kosuke OTUBO, Kazuo OGURA, Mitsuhisa YAMAKAWA and Yusuke TAKASHIMA, Plasma Fusion Res. 5, S1047 (2010).