Intermittent magnetic fluctuations associated with high-temperature bubbles in an ECR plasma

Shinji Yoshimura, Kenichiro Terasaka, Masayoshi Y. Tanaka

Research output: Contribution to journalArticle

Abstract

Magnetic probe measurement has been performed in a cylindrical electron cyclotron resonance plasma in which localized high temperature electron region, i.e. high-temperature bubble, has been generated intermittently. It is found that the high-temperature bubble is accompanied by a pulsed magnetic fluctuation perpendicular to the external magnetic field. Polarities of the magnetic fluctuation suggest that it should be induced by a transient upstream electric current. This hypothesis has been validated by a simultaneous increase of electron flux in the downstream direction. No enhancement of electron flux in the upstream direction has been observed even under the existence of the bubbles. The result suggests that the electron velocity distribution function in the bubble should be an asymmetric one, which gives rise to an effective upstream electric current.

Original languageEnglish
Article number3401081
JournalPlasma and Fusion Research
Volume14
Issue numberSpecialissue2
DOIs
Publication statusPublished - Jan 1 2019

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bubbles
upstream
electron flux
electric current
magnetic probes
electron cyclotron resonance
polarity
electrons
velocity distribution
distribution functions
augmentation
magnetic fields

All Science Journal Classification (ASJC) codes

  • Condensed Matter Physics

Cite this

Intermittent magnetic fluctuations associated with high-temperature bubbles in an ECR plasma. / Yoshimura, Shinji; Terasaka, Kenichiro; Tanaka, Masayoshi Y.

In: Plasma and Fusion Research, Vol. 14, No. Specialissue2, 3401081, 01.01.2019.

Research output: Contribution to journalArticle

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