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.
| Original language | English |
|---|---|
| Pages (from-to) | 1649-1658 |
| Number of pages | 10 |
| Journal | Nuclear Fusion |
| Volume | 39 |
| Issue number | Special Issu |
| DOIs | |
| Publication status | Published - Dec 1 1999 |
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All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics
- Condensed Matter Physics
Cite this
Transition from L mode to high ion temperature mode in CHS heliotron/torsatron plasmas. / 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.; Morita, S.; Nomura, I.; Ohdachi, S.; Sasao, M.; Shimizu, A.; Takagi, S.; Takahashi, C.; Takayama, S.; Takechi, M.; Toi, K.; Tsumori, K.; Watari, T.
In: Nuclear Fusion, Vol. 39, No. Special Issu, 01.12.1999, p. 1649-1658.Research output: Contribution to journal › Article
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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 - 1999/12/1
Y1 - 1999/12/1
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.
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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 -