Role of electric field curvature in the formation of edge transport barrier in the JT-60U tokamak

K. Kamiya, K. Itoh, S. I. Itoh, K. Ida, T. Kobayashi

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Based on the high-resolution spectroscopic measurements of the radial electric field (E r) in the JT-60U tokamak, we have identified the mechanisms centered around the role of the E r-curvature on the edge transport barrier (ETB) formation. In addition, we recognized a new role of the E r-shear for the expansion of pedestal width, compensating an unfavorable effect of the E r-curvature having its sign dependence on the turbulence transport. We found a new interesting phenomenon of very slow out-of-phase oscillations between the E r and ion temperature gradient in the frequency range of 30-50 Hz, preceding the slow L-H transition, which can demonstrate a causality test of the ETB formation in association with the non-uniformity E r-effects. A critical condition for the E r-bifurcations is also discussed.

Original languageEnglish
Article number014023
JournalPlasma Physics and Controlled Fusion
Volume60
Issue number1
DOIs
Publication statusPublished - Jan 2018

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Thermal gradients
Turbulence
curvature
Electric fields
electric fields
Ions
ion temperature
nonuniformity
temperature gradients
frequency ranges
turbulence
shear
oscillations
expansion
high resolution
temperature

All Science Journal Classification (ASJC) codes

  • Nuclear Energy and Engineering
  • Condensed Matter Physics

Cite this

Role of electric field curvature in the formation of edge transport barrier in the JT-60U tokamak. / Kamiya, K.; Itoh, K.; Itoh, S. I.; Ida, K.; Kobayashi, T.

In: Plasma Physics and Controlled Fusion, Vol. 60, No. 1, 014023, 01.2018.

Research output: Contribution to journalArticle

Kamiya, K. ; Itoh, K. ; Itoh, S. I. ; Ida, K. ; Kobayashi, T. / Role of electric field curvature in the formation of edge transport barrier in the JT-60U tokamak. In: Plasma Physics and Controlled Fusion. 2018 ; Vol. 60, No. 1.
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