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Title: Slow Transition of Energy Transport in High-Temperature Plasmas

Abstract

A new slow transition process for energy transport in magnetically confined plasmas is reported. The slow transition is characterized by the change between two metastable transport conditions characterized by a weak and a strong electron temperature (T{sub e}) dependence of normalized heat flux. These two branches are found to merge at the critical T{sub e} gradient. In metastable transport, the derivative of normalized heat flux to the T{sub e} gradient, {partial_derivative}(Q{sub e}/n{sub e})/{partial_derivative}(-{nabla}T{sub e}), is positive, while it becomes negative during the transition phase. The time for the transition increases as the normalized T{sub e} gradient is increased and exceeds the transport time scale characterized by the global energy confinement time.

Authors:
; ; ; ; ; ; ; ; ; ; ; ; ; ;  [1]
  1. National Institute for Fusion Sciences, Toki, Gifu 509-5292 (Japan)
Publication Date:
OSTI Identifier:
20777121
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 96; Journal Issue: 12; Other Information: DOI: 10.1103/PhysRevLett.96.125006; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; CONFINEMENT TIME; ELECTRON TEMPERATURE; HEAT FLUX; HOT PLASMA; ION TEMPERATURE; PLASMA CONFINEMENT; PLASMA DENSITY

Citation Formats

Ida, K., Inagaki, S., Sakamoto, R., Tanaka, K., Funaba, H., Takeiri, Y., Ikeda, K., Michael, C., Tokuzawa, T., Yamada, H., Nagayama, Y., Itoh, K., Kaneko, O., Komori, A., and Motojima, O. Slow Transition of Energy Transport in High-Temperature Plasmas. United States: N. p., 2006. Web. doi:10.1103/PhysRevLett.96.125006.
Ida, K., Inagaki, S., Sakamoto, R., Tanaka, K., Funaba, H., Takeiri, Y., Ikeda, K., Michael, C., Tokuzawa, T., Yamada, H., Nagayama, Y., Itoh, K., Kaneko, O., Komori, A., & Motojima, O. Slow Transition of Energy Transport in High-Temperature Plasmas. United States. doi:10.1103/PhysRevLett.96.125006.
Ida, K., Inagaki, S., Sakamoto, R., Tanaka, K., Funaba, H., Takeiri, Y., Ikeda, K., Michael, C., Tokuzawa, T., Yamada, H., Nagayama, Y., Itoh, K., Kaneko, O., Komori, A., and Motojima, O. Fri . "Slow Transition of Energy Transport in High-Temperature Plasmas". United States. doi:10.1103/PhysRevLett.96.125006.
@article{osti_20777121,
title = {Slow Transition of Energy Transport in High-Temperature Plasmas},
author = {Ida, K. and Inagaki, S. and Sakamoto, R. and Tanaka, K. and Funaba, H. and Takeiri, Y. and Ikeda, K. and Michael, C. and Tokuzawa, T. and Yamada, H. and Nagayama, Y. and Itoh, K. and Kaneko, O. and Komori, A. and Motojima, O.},
abstractNote = {A new slow transition process for energy transport in magnetically confined plasmas is reported. The slow transition is characterized by the change between two metastable transport conditions characterized by a weak and a strong electron temperature (T{sub e}) dependence of normalized heat flux. These two branches are found to merge at the critical T{sub e} gradient. In metastable transport, the derivative of normalized heat flux to the T{sub e} gradient, {partial_derivative}(Q{sub e}/n{sub e})/{partial_derivative}(-{nabla}T{sub e}), is positive, while it becomes negative during the transition phase. The time for the transition increases as the normalized T{sub e} gradient is increased and exceeds the transport time scale characterized by the global energy confinement time.},
doi = {10.1103/PhysRevLett.96.125006},
journal = {Physical Review Letters},
number = 12,
volume = 96,
place = {United States},
year = {Fri Mar 31 00:00:00 EST 2006},
month = {Fri Mar 31 00:00:00 EST 2006}
}
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