Effect of Reflections on Nonstationary Gyrotron Oscillations

Markus I. Airila, Pia Kåll

Research output: Contribution to journalArticleScientificpeer-review

10 Citations (Scopus)

Abstract

We present an extension of the self-consistent time-dependent theory describing nonstationary processes in gyrotrons to allow for reflections. Different mathematical descriptions of partial reflection of the output signal are compared, and numerical algorithms for analyzing them are given. Using a novel description, we have computed a map of gyrotron oscillations which identifies the regimes of stationary, periodically modulated, and chaotic oscillations in the plane of generalized gyrotron variables when reflection is present. In general, reflections drive the gyrotron into quasi-periodic oscillations instead of chaos, but also the threshold current for chaotic oscillations decreases somewhat. The results can be exploited in the development of high-power gyrotrons for electron cyclotron resonance heating and electron cyclotron current drive of fusion plasmas, but also in low-power applications, where chaotic oscillations might be useful.

Original languageEnglish
Pages (from-to)522-528
Number of pages7
JournalIEEE Transactions on Microwave Theory and Techniques
Volume52
Issue number2
DOIs
Publication statusPublished - 1 Feb 2004
MoE publication typeA1 Journal article-refereed

Fingerprint

Gyrotrons
oscillations
cyclotron resonance devices
Electron cyclotron resonance
Cyclotrons
Chaos theory
electron cyclotron resonance
Fusion reactions
threshold currents
cyclotrons
chaos
Plasmas
Heating
fusion
Electrons
heating
output
electrons

Keywords

  • Chaos
  • Gyrotron
  • Quasi-periodicity
  • Reflections

Cite this

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Effect of Reflections on Nonstationary Gyrotron Oscillations. / Airila, Markus I.; Kåll, Pia.

In: IEEE Transactions on Microwave Theory and Techniques, Vol. 52, No. 2, 01.02.2004, p. 522-528.

Research output: Contribution to journalArticleScientificpeer-review

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