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Title: Time-domain theory of gyrotron traveling wave amplifiers operating at grazing incidence

Abstract

Time-domain theory of the gyrotron traveling wave tube (gyro-TWT) operating at grazing incidence has been developed. The theory is based on a description of wave propagation by a parabolic equation. The results of the simulations are compared with experimental results of the observation of subnanosecond pulse amplification in a gyro-TWT consisting of three gain sections separated by severs. The theory developed can also be used successfully for a description of amplification of monochromatic signals.

Authors:
 [1];  [2]; ; ;  [1]
  1. Institute of Applied Physics of the Russian Academy of Sciences, 46, Ul'yanov St., Nizhny Novgorod (Russian Federation)
  2. (Russian Federation)
Publication Date:
OSTI Identifier:
22408024
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 1; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; AMPLIFIERS; COMPARATIVE EVALUATIONS; EXPERIMENTAL DATA; INCIDENCE ANGLE; MONOCHROMATIC RADIATION; PULSES; SIGNALS; SIMULATION; TRAVELLING WAVE TUBES; WAVE PROPAGATION

Citation Formats

Ginzburg, N. S., E-mail: ginzburg@appl.sci-nnov.ru, Nizhny Novgorod State University, Gagarin Ave., 23, 603950 Nizhny Novgorod, Sergeev, A. S., Zotova, I. V., and Zheleznov, I. V. Time-domain theory of gyrotron traveling wave amplifiers operating at grazing incidence. United States: N. p., 2015. Web. doi:10.1063/1.4906364.
Ginzburg, N. S., E-mail: ginzburg@appl.sci-nnov.ru, Nizhny Novgorod State University, Gagarin Ave., 23, 603950 Nizhny Novgorod, Sergeev, A. S., Zotova, I. V., & Zheleznov, I. V. Time-domain theory of gyrotron traveling wave amplifiers operating at grazing incidence. United States. doi:10.1063/1.4906364.
Ginzburg, N. S., E-mail: ginzburg@appl.sci-nnov.ru, Nizhny Novgorod State University, Gagarin Ave., 23, 603950 Nizhny Novgorod, Sergeev, A. S., Zotova, I. V., and Zheleznov, I. V. Thu . "Time-domain theory of gyrotron traveling wave amplifiers operating at grazing incidence". United States. doi:10.1063/1.4906364.
@article{osti_22408024,
title = {Time-domain theory of gyrotron traveling wave amplifiers operating at grazing incidence},
author = {Ginzburg, N. S., E-mail: ginzburg@appl.sci-nnov.ru and Nizhny Novgorod State University, Gagarin Ave., 23, 603950 Nizhny Novgorod and Sergeev, A. S. and Zotova, I. V. and Zheleznov, I. V.},
abstractNote = {Time-domain theory of the gyrotron traveling wave tube (gyro-TWT) operating at grazing incidence has been developed. The theory is based on a description of wave propagation by a parabolic equation. The results of the simulations are compared with experimental results of the observation of subnanosecond pulse amplification in a gyro-TWT consisting of three gain sections separated by severs. The theory developed can also be used successfully for a description of amplification of monochromatic signals.},
doi = {10.1063/1.4906364},
journal = {Physics of Plasmas},
number = 1,
volume = 22,
place = {United States},
year = {Thu Jan 15 00:00:00 EST 2015},
month = {Thu Jan 15 00:00:00 EST 2015}
}
  • A linear theory of large-orbit gyrotron traveling wave amplifiers (gyro-TWAs), which can be applied to analyze the effect of electron beam misalignment, is developed by specializing the corresponding theory of small-orbit gyro-TWAs. The linear theory is validated by comparing with a nonlinear theory. Numerical results show that beam misalignment can reduce linear gain and amplification bandwidth of large-orbit gyro-TWAs and increase the starting length of large-orbit gyro-BWOs for modes in accordance with the mode-selective condition. In addition, beam misalignment can also break the limitation of mode-selective condition and make the instability problem more complex.
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