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Title: TWANG-PIC, a novel gyro-averaged one-dimensional particle-in-cell code for interpretation of gyrotron experiments

Abstract

A new gyrotron simulation code for simulating the beam-wave interaction using a monomode time-dependent self-consistent model is presented. The new code TWANG-PIC is derived from the trajectory-based code TWANG by describing the electron motion in a gyro-averaged one-dimensional Particle-In-Cell (PIC) approach. In comparison to common PIC-codes, it is distinguished by its computation speed, which makes its use in parameter scans and in experiment interpretation possible. A benchmark of the new code is presented as well as a comparative study between the two codes. This study shows that the inclusion of a time-dependence in the electron equations, as it is the case in the PIC-approach, is mandatory for simulating any kind of non-stationary oscillations in gyrotrons. Finally, the new code is compared with experimental results and some implications of the violated model assumptions in the TWANG code are disclosed for a gyrotron experiment in which non-stationary regimes have been observed and for a critical case that is of interest in high power gyrotron development.

Authors:
; ; ; ; ;  [1];  [2]
  1. École Polytechnique Fédérale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas (CRPP), CH-1015 Lausanne (Switzerland)
  2. Institut de Physique Nucléaire (IPN), F-91406 Orsay (France)
Publication Date:
OSTI Identifier:
22490947
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 6; Other Information: (c) 2015 EURATOM; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; BENCHMARKS; COMPARATIVE EVALUATIONS; COMPUTER CODES; COMPUTERIZED SIMULATION; ELECTRONS; MICROWAVE AMPLIFIERS; ONE-DIMENSIONAL CALCULATIONS; OSCILLATIONS; TIME DEPENDENCE; TRAJECTORIES

Citation Formats

Braunmueller, F., E-mail: falk.braunmueller@epfl.ch, Tran, T. M., Alberti, S., Genoud, J., Hogge, J.-Ph., Tran, M. Q., and Vuillemin, Q. TWANG-PIC, a novel gyro-averaged one-dimensional particle-in-cell code for interpretation of gyrotron experiments. United States: N. p., 2015. Web. doi:10.1063/1.4923299.
Braunmueller, F., E-mail: falk.braunmueller@epfl.ch, Tran, T. M., Alberti, S., Genoud, J., Hogge, J.-Ph., Tran, M. Q., & Vuillemin, Q. TWANG-PIC, a novel gyro-averaged one-dimensional particle-in-cell code for interpretation of gyrotron experiments. United States. doi:10.1063/1.4923299.
Braunmueller, F., E-mail: falk.braunmueller@epfl.ch, Tran, T. M., Alberti, S., Genoud, J., Hogge, J.-Ph., Tran, M. Q., and Vuillemin, Q. Mon . "TWANG-PIC, a novel gyro-averaged one-dimensional particle-in-cell code for interpretation of gyrotron experiments". United States. doi:10.1063/1.4923299.
@article{osti_22490947,
title = {TWANG-PIC, a novel gyro-averaged one-dimensional particle-in-cell code for interpretation of gyrotron experiments},
author = {Braunmueller, F., E-mail: falk.braunmueller@epfl.ch and Tran, T. M. and Alberti, S. and Genoud, J. and Hogge, J.-Ph. and Tran, M. Q. and Vuillemin, Q.},
abstractNote = {A new gyrotron simulation code for simulating the beam-wave interaction using a monomode time-dependent self-consistent model is presented. The new code TWANG-PIC is derived from the trajectory-based code TWANG by describing the electron motion in a gyro-averaged one-dimensional Particle-In-Cell (PIC) approach. In comparison to common PIC-codes, it is distinguished by its computation speed, which makes its use in parameter scans and in experiment interpretation possible. A benchmark of the new code is presented as well as a comparative study between the two codes. This study shows that the inclusion of a time-dependence in the electron equations, as it is the case in the PIC-approach, is mandatory for simulating any kind of non-stationary oscillations in gyrotrons. Finally, the new code is compared with experimental results and some implications of the violated model assumptions in the TWANG code are disclosed for a gyrotron experiment in which non-stationary regimes have been observed and for a critical case that is of interest in high power gyrotron development.},
doi = {10.1063/1.4923299},
journal = {Physics of Plasmas},
number = 6,
volume = 22,
place = {United States},
year = {Mon Jun 15 00:00:00 EDT 2015},
month = {Mon Jun 15 00:00:00 EDT 2015}
}
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