Transition phenomena and thermal transport properties in LHD plasmas with an electron internal transport barrier

T. Shimozuma, S. Kubo, H. Idei, S. Inagaki, N. Tamura, T. Tokuzawa, T. Morisaki, K. Y. Watanabe, K. Ida, I. Yamada, K. Narihara, S. Muto, M. Yokoyama, Y. Yoshimura, T. Notake, K. Ohkubo, T. Seki, K. Saito, R. Kumazawa, T. MutohT. Watari, A. Komori

Research output: Contribution to journalArticle

28 Citations (Scopus)

Abstract

Two types of improved core confinement were observed during centrally focused electron cyclotron heating (ECH) into plasmas sustained by counter (CNTR) and Co neutral beam injections (NBI) in the Large Helical Device. The CNTR NBI plasma displayed transition phenomena to the high-electron-temperature state and had a clear electron internal transport barrier, while the Co NBI plasma did not show a clear transition or an ECH power threshold but showed broad high temperature profiles with moderate temperature gradient. This indicated that the Co NBI plasma with additional ECH also had an improved core confinement. The electron heat transport characteristics of these plasmas were directly investigated using heat pulse propagation excited by modulated ECH. These effects appear to be related to the m/n = 2/1 rational surface or the island induced by NBI beam-driven current.

Original languageEnglish
Pages (from-to)1396-1403
Number of pages8
JournalNuclear Fusion
Volume45
Issue number11
DOIs
Publication statusPublished - Oct 25 2005

Fingerprint

beam injection
neutral beams
electron cyclotron heating
transport properties
electrons
counters
heat
temperature profiles
temperature gradients
electron energy
thresholds
propagation
pulses

All Science Journal Classification (ASJC) codes

  • Nuclear and High Energy Physics
  • Condensed Matter Physics

Cite this

Transition phenomena and thermal transport properties in LHD plasmas with an electron internal transport barrier. / Shimozuma, T.; Kubo, S.; Idei, H.; Inagaki, S.; Tamura, N.; Tokuzawa, T.; Morisaki, T.; Watanabe, K. Y.; Ida, K.; Yamada, I.; Narihara, K.; Muto, S.; Yokoyama, M.; Yoshimura, Y.; Notake, T.; Ohkubo, K.; Seki, T.; Saito, K.; Kumazawa, R.; Mutoh, T.; Watari, T.; Komori, A.

In: Nuclear Fusion, Vol. 45, No. 11, 25.10.2005, p. 1396-1403.

Research output: Contribution to journalArticle

Shimozuma, T, Kubo, S, Idei, H, Inagaki, S, Tamura, N, Tokuzawa, T, Morisaki, T, Watanabe, KY, Ida, K, Yamada, I, Narihara, K, Muto, S, Yokoyama, M, Yoshimura, Y, Notake, T, Ohkubo, K, Seki, T, Saito, K, Kumazawa, R, Mutoh, T, Watari, T & Komori, A 2005, 'Transition phenomena and thermal transport properties in LHD plasmas with an electron internal transport barrier', Nuclear Fusion, vol. 45, no. 11, pp. 1396-1403. https://doi.org/10.1088/0029-5515/45/11/021
Shimozuma, T. ; Kubo, S. ; Idei, H. ; Inagaki, S. ; Tamura, N. ; Tokuzawa, T. ; Morisaki, T. ; Watanabe, K. Y. ; Ida, K. ; Yamada, I. ; Narihara, K. ; Muto, S. ; Yokoyama, M. ; Yoshimura, Y. ; Notake, T. ; Ohkubo, K. ; Seki, T. ; Saito, K. ; Kumazawa, R. ; Mutoh, T. ; Watari, T. ; Komori, A. / Transition phenomena and thermal transport properties in LHD plasmas with an electron internal transport barrier. In: Nuclear Fusion. 2005 ; Vol. 45, No. 11. pp. 1396-1403.
@article{5cbcf6a6c2f44ce8867e8dfff0286d21,
title = "Transition phenomena and thermal transport properties in LHD plasmas with an electron internal transport barrier",
abstract = "Two types of improved core confinement were observed during centrally focused electron cyclotron heating (ECH) into plasmas sustained by counter (CNTR) and Co neutral beam injections (NBI) in the Large Helical Device. The CNTR NBI plasma displayed transition phenomena to the high-electron-temperature state and had a clear electron internal transport barrier, while the Co NBI plasma did not show a clear transition or an ECH power threshold but showed broad high temperature profiles with moderate temperature gradient. This indicated that the Co NBI plasma with additional ECH also had an improved core confinement. The electron heat transport characteristics of these plasmas were directly investigated using heat pulse propagation excited by modulated ECH. These effects appear to be related to the m/n = 2/1 rational surface or the island induced by NBI beam-driven current.",
author = "T. Shimozuma and S. Kubo and H. Idei and S. Inagaki and N. Tamura and T. Tokuzawa and T. Morisaki and Watanabe, {K. Y.} and K. Ida and I. Yamada and K. Narihara and S. Muto and M. Yokoyama and Y. Yoshimura and T. Notake and K. Ohkubo and T. Seki and K. Saito and R. Kumazawa and T. Mutoh and T. Watari and A. Komori",
year = "2005",
month = "10",
day = "25",
doi = "10.1088/0029-5515/45/11/021",
language = "English",
volume = "45",
pages = "1396--1403",
journal = "Nuclear Fusion",
issn = "0029-5515",
publisher = "IOP Publishing Ltd.",
number = "11",

}

TY - JOUR

T1 - Transition phenomena and thermal transport properties in LHD plasmas with an electron internal transport barrier

AU - Shimozuma, T.

AU - Kubo, S.

AU - Idei, H.

AU - Inagaki, S.

AU - Tamura, N.

AU - Tokuzawa, T.

AU - Morisaki, T.

AU - Watanabe, K. Y.

AU - Ida, K.

AU - Yamada, I.

AU - Narihara, K.

AU - Muto, S.

AU - Yokoyama, M.

AU - Yoshimura, Y.

AU - Notake, T.

AU - Ohkubo, K.

AU - Seki, T.

AU - Saito, K.

AU - Kumazawa, R.

AU - Mutoh, T.

AU - Watari, T.

AU - Komori, A.

PY - 2005/10/25

Y1 - 2005/10/25

N2 - Two types of improved core confinement were observed during centrally focused electron cyclotron heating (ECH) into plasmas sustained by counter (CNTR) and Co neutral beam injections (NBI) in the Large Helical Device. The CNTR NBI plasma displayed transition phenomena to the high-electron-temperature state and had a clear electron internal transport barrier, while the Co NBI plasma did not show a clear transition or an ECH power threshold but showed broad high temperature profiles with moderate temperature gradient. This indicated that the Co NBI plasma with additional ECH also had an improved core confinement. The electron heat transport characteristics of these plasmas were directly investigated using heat pulse propagation excited by modulated ECH. These effects appear to be related to the m/n = 2/1 rational surface or the island induced by NBI beam-driven current.

AB - Two types of improved core confinement were observed during centrally focused electron cyclotron heating (ECH) into plasmas sustained by counter (CNTR) and Co neutral beam injections (NBI) in the Large Helical Device. The CNTR NBI plasma displayed transition phenomena to the high-electron-temperature state and had a clear electron internal transport barrier, while the Co NBI plasma did not show a clear transition or an ECH power threshold but showed broad high temperature profiles with moderate temperature gradient. This indicated that the Co NBI plasma with additional ECH also had an improved core confinement. The electron heat transport characteristics of these plasmas were directly investigated using heat pulse propagation excited by modulated ECH. These effects appear to be related to the m/n = 2/1 rational surface or the island induced by NBI beam-driven current.

UR - http://www.scopus.com/inward/record.url?scp=33750350129&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33750350129&partnerID=8YFLogxK

U2 - 10.1088/0029-5515/45/11/021

DO - 10.1088/0029-5515/45/11/021

M3 - Article

AN - SCOPUS:33750350129

VL - 45

SP - 1396

EP - 1403

JO - Nuclear Fusion

JF - Nuclear Fusion

SN - 0029-5515

IS - 11

ER -