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Title: Nonlinear theory of beam-wave interaction in the pasotron with a phase-mixed electron beam

Abstract

The nonlinear theory describing the interaction processes in traveling-wave-amplifier (TWT) and backward-wave-oscillator (BWO) configurations of pasotrons is developed. It is shown that space charge forces in electron bunches formed in the process of beam-wave interaction in the pasotron play a role completely different from that in linear-beam devices with a strong magnetic focusing of electron beams. While in the latter devices the space charge forces limit the device efficiency due to saturation of the axial bunching, in the pasotron they do not destroy electron bunches but cause the radial expansion of them, which may increase device efficiency. The role of these forces is compared with the ion focusing and the radial electric field of the wave, and it is shown that, under certain conditions, it may dominate. The efficiency of the pasotron-TWT with a phase-mixed beam well focused at the entrance may exceed 50%. In the pasotron-BWO, the efficiency is lower (up to 26% in the case studied), but it can grow as the equivalent of the Pierce gain parameter increases.

Authors:
;  [1];  [2]
  1. Technion, Haifa, 32000 (Israel)
  2. (United States)
Publication Date:
OSTI Identifier:
20782516
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 13; Journal Issue: 2; Other Information: DOI: 10.1063/1.2172924; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; AMPLIFIERS; BEAM BUNCHING; EFFICIENCY; ELECTRIC FIELDS; ELECTRON BEAMS; ELECTRONS; FOCUSING; GAIN; IONS; NONLINEAR PROBLEMS; OSCILLATORS; SPACE CHARGE; TRAVELLING WAVES

Citation Formats

Bliokh, Yu.P., Nusinovich, G.S., and Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland, 20742-3511. Nonlinear theory of beam-wave interaction in the pasotron with a phase-mixed electron beam. United States: N. p., 2006. Web. doi:10.1063/1.2172924.
Bliokh, Yu.P., Nusinovich, G.S., & Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland, 20742-3511. Nonlinear theory of beam-wave interaction in the pasotron with a phase-mixed electron beam. United States. doi:10.1063/1.2172924.
Bliokh, Yu.P., Nusinovich, G.S., and Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland, 20742-3511. Wed . "Nonlinear theory of beam-wave interaction in the pasotron with a phase-mixed electron beam". United States. doi:10.1063/1.2172924.
@article{osti_20782516,
title = {Nonlinear theory of beam-wave interaction in the pasotron with a phase-mixed electron beam},
author = {Bliokh, Yu.P. and Nusinovich, G.S. and Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland, 20742-3511},
abstractNote = {The nonlinear theory describing the interaction processes in traveling-wave-amplifier (TWT) and backward-wave-oscillator (BWO) configurations of pasotrons is developed. It is shown that space charge forces in electron bunches formed in the process of beam-wave interaction in the pasotron play a role completely different from that in linear-beam devices with a strong magnetic focusing of electron beams. While in the latter devices the space charge forces limit the device efficiency due to saturation of the axial bunching, in the pasotron they do not destroy electron bunches but cause the radial expansion of them, which may increase device efficiency. The role of these forces is compared with the ion focusing and the radial electric field of the wave, and it is shown that, under certain conditions, it may dominate. The efficiency of the pasotron-TWT with a phase-mixed beam well focused at the entrance may exceed 50%. In the pasotron-BWO, the efficiency is lower (up to 26% in the case studied), but it can grow as the equivalent of the Pierce gain parameter increases.},
doi = {10.1063/1.2172924},
journal = {Physics of Plasmas},
number = 2,
volume = 13,
place = {United States},
year = {Wed Feb 15 00:00:00 EST 2006},
month = {Wed Feb 15 00:00:00 EST 2006}
}
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