Transition from L mode to high ion temperature mode in CHS heliotron/torsatron plasmas

K. Ida; M. Osakabe; K. Tanaka; T. Minami; S. Nishimura; S. Okamura; A. Fujisawa; K. Yamazaki; Y. Yoshimura; S. Kubo; R. Akiyama; D. S. Darrow; H. Idei; H. Iguchi; M. Isobe; S. Kado; T. Kondo; S. Lee; K. Matsuoka; S. Morita; I. Nomura; S. Ohdachi; M. Sasao; A. Shimizu; S. Takagi; C. Takahashi; S. Takayama; M. Takechi; K. Toi; K. Tsumori; T. Watari

doi:10.1088/0029-5515/39/11Y/304

Transition from L mode to high ion temperature mode in CHS heliotron/torsatron plasmas

K. Ida, M. Osakabe, K. Tanaka, T. Minami, S. Nishimura, S. Okamura, A. Fujisawa, K. Yamazaki, Y. Yoshimura, S. Kubo, R. Akiyama, D. S. Darrow, H. Idei, H. Iguchi, M. Isobe, S. Kado, T. Kondo, S. Lee, K. Matsuoka, S. MoritaI. Nomura, S. Ohdachi, M. Sasao, A. Shimizu, S. Takagi, C. Takahashi, S. Takayama, M. Takechi, K. Toi, K. Tsumori, T. Watari

Research output: Contribution to journal › Article › peer-review

21 Citations (Scopus)

Abstract

A high ion temperature (T_i) mode is observed for neutral beam heated plasmas in the Compact Helical System (CHS) heliotron/torsatron. The high T_i mode plasma is characterized by a high central ion temperature, T_i(O), and is associated with a peaked electron density profile produced by neutral beam fuelling with low wall recycling. Transition from L mode to high T_i mode has been studied in CHS. T_i(0) in the high T_i mode discharges reaches 1 keV, which is 2.5 times higher than that in the L mode discharges. The ion thermal diffusivity is significantly reduced by a factor of more than 2-3 in the high T_i mode plasma. The ion loss cone is observed in neutral particle flux in the energy range 1-6 keV with a narrow range of pitch angle (90°±20°) in the high T_i mode. However, the degradation of ion energy confinement due to this loss cone is negligible.

Original language	English
Pages (from-to)	1649-1658
Number of pages	10
Journal	Nuclear Fusion
Volume	39
Issue number	Special Issu
DOIs	https://doi.org/10.1088/0029-5515/39/11Y/304
Publication status	Published - 1999
Externally published	Yes

All Science Journal Classification (ASJC) codes

Nuclear and High Energy Physics
Condensed Matter Physics

Access to Document

10.1088/0029-5515/39/11Y/304

Cite this

Ida, K., Osakabe, M., Tanaka, K., Minami, T., Nishimura, S., Okamura, S., Fujisawa, A., Yamazaki, K., Yoshimura, Y., Kubo, S., Akiyama, R., Darrow, D. S., Idei, H., Iguchi, H., Isobe, M., Kado, S., Kondo, T., Lee, S., Matsuoka, K., ... Watari, T. (1999). Transition from L mode to high ion temperature mode in CHS heliotron/torsatron plasmas. Nuclear Fusion, 39(Special Issu), 1649-1658. https://doi.org/10.1088/0029-5515/39/11Y/304

Ida, K, Osakabe, M, Tanaka, K, Minami, T, Nishimura, S, Okamura, S, Fujisawa, A, Yamazaki, K, Yoshimura, Y, Kubo, S, Akiyama, R, Darrow, DS, Idei, H, Iguchi, H, Isobe, M, Kado, S, Kondo, T, Lee, S, Matsuoka, K, Morita, S, Nomura, I, Ohdachi, S, Sasao, M, Shimizu, A, Takagi, S, Takahashi, C, Takayama, S, Takechi, M, Toi, K, Tsumori, K & Watari, T 1999, 'Transition from L mode to high ion temperature mode in CHS heliotron/torsatron plasmas', Nuclear Fusion, vol. 39, no. Special Issu, pp. 1649-1658. https://doi.org/10.1088/0029-5515/39/11Y/304

@article{934253398678413bac41543073687e08,

title = "Transition from L mode to high ion temperature mode in CHS heliotron/torsatron plasmas",

abstract = "A high ion temperature (Ti) mode is observed for neutral beam heated plasmas in the Compact Helical System (CHS) heliotron/torsatron. The high Ti mode plasma is characterized by a high central ion temperature, Ti(O), and is associated with a peaked electron density profile produced by neutral beam fuelling with low wall recycling. Transition from L mode to high Ti mode has been studied in CHS. Ti(0) in the high Ti mode discharges reaches 1 keV, which is 2.5 times higher than that in the L mode discharges. The ion thermal diffusivity is significantly reduced by a factor of more than 2-3 in the high Ti mode plasma. The ion loss cone is observed in neutral particle flux in the energy range 1-6 keV with a narrow range of pitch angle (90°±20°) in the high Ti mode. However, the degradation of ion energy confinement due to this loss cone is negligible.",

author = "K. Ida and M. Osakabe and K. Tanaka and T. Minami and S. Nishimura and S. Okamura and A. Fujisawa and K. Yamazaki and Y. Yoshimura and S. Kubo and R. Akiyama and Darrow, {D. S.} and H. Idei and H. Iguchi and M. Isobe and S. Kado and T. Kondo and S. Lee and K. Matsuoka and S. Morita and I. Nomura and S. Ohdachi and M. Sasao and A. Shimizu and S. Takagi and C. Takahashi and S. Takayama and M. Takechi and K. Toi and K. Tsumori and T. Watari",

year = "1999",

doi = "10.1088/0029-5515/39/11Y/304",

language = "English",

volume = "39",

pages = "1649--1658",

journal = "Nuclear Fusion",

issn = "0029-5515",

publisher = "IOP Publishing Ltd.",

number = "Special Issu",

}

TY - JOUR

T1 - Transition from L mode to high ion temperature mode in CHS heliotron/torsatron plasmas

AU - Ida, K.

AU - Osakabe, M.

AU - Tanaka, K.

AU - Minami, T.

AU - Nishimura, S.

AU - Okamura, S.

AU - Fujisawa, A.

AU - Yamazaki, K.

AU - Yoshimura, Y.

AU - Kubo, S.

AU - Akiyama, R.

AU - Darrow, D. S.

AU - Idei, H.

AU - Iguchi, H.

AU - Isobe, M.

AU - Kado, S.

AU - Kondo, T.

AU - Lee, S.

AU - Matsuoka, K.

AU - Morita, S.

AU - Nomura, I.

AU - Ohdachi, S.

AU - Sasao, M.

AU - Shimizu, A.

AU - Takagi, S.

AU - Takahashi, C.

AU - Takayama, S.

AU - Takechi, M.

AU - Toi, K.

AU - Tsumori, K.

AU - Watari, T.

PY - 1999

Y1 - 1999

N2 - A high ion temperature (Ti) mode is observed for neutral beam heated plasmas in the Compact Helical System (CHS) heliotron/torsatron. The high Ti mode plasma is characterized by a high central ion temperature, Ti(O), and is associated with a peaked electron density profile produced by neutral beam fuelling with low wall recycling. Transition from L mode to high Ti mode has been studied in CHS. Ti(0) in the high Ti mode discharges reaches 1 keV, which is 2.5 times higher than that in the L mode discharges. The ion thermal diffusivity is significantly reduced by a factor of more than 2-3 in the high Ti mode plasma. The ion loss cone is observed in neutral particle flux in the energy range 1-6 keV with a narrow range of pitch angle (90°±20°) in the high Ti mode. However, the degradation of ion energy confinement due to this loss cone is negligible.

AB - A high ion temperature (Ti) mode is observed for neutral beam heated plasmas in the Compact Helical System (CHS) heliotron/torsatron. The high Ti mode plasma is characterized by a high central ion temperature, Ti(O), and is associated with a peaked electron density profile produced by neutral beam fuelling with low wall recycling. Transition from L mode to high Ti mode has been studied in CHS. Ti(0) in the high Ti mode discharges reaches 1 keV, which is 2.5 times higher than that in the L mode discharges. The ion thermal diffusivity is significantly reduced by a factor of more than 2-3 in the high Ti mode plasma. The ion loss cone is observed in neutral particle flux in the energy range 1-6 keV with a narrow range of pitch angle (90°±20°) in the high Ti mode. However, the degradation of ion energy confinement due to this loss cone is negligible.

UR - http://www.scopus.com/inward/record.url?scp=12944311030&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=12944311030&partnerID=8YFLogxK

U2 - 10.1088/0029-5515/39/11Y/304

DO - 10.1088/0029-5515/39/11Y/304

M3 - Article

AN - SCOPUS:12944311030

VL - 39

SP - 1649

EP - 1658

JO - Nuclear Fusion

JF - Nuclear Fusion

SN - 0029-5515

IS - Special Issu

ER -

Transition from L mode to high ion temperature mode in CHS heliotron/torsatron plasmas

Abstract

All Science Journal Classification (ASJC) codes

Access to Document

Other files and links

Fingerprint

Cite this