23P028-P
Measurement of impurity ion temperature using
charge exchange recombination spectroscopy in Heliotron J
ヘリオトロンJ における荷電交換再結合分光による不純物イオン温度分布計測
Takayuki Minami1, Shinji Kobayashi2, Hyunyong Lee 1, Shinichiro Kado3, Tohru Mizuuchi2,Kazunobu Nagasaki2, Hiroyuki Okada2, Takashi Minami2, Satoshi Yamamoto2,Shinsuke Ohshima5,
Tomotaka Harada6, Tasuku Kagawa1, Kiyofumi Mukai1, Linge Zang 1, Shohei Arai1,Hiroaki Yashiro1, Hiroto Watada1, Yoshinobu Wada1, Sadayoshi Murakami4, Yuji Nakamura1,Kiyoshi Hanatani2, Shigeru Konoshima2, Fumimichi Sano2
南 貴之1, 小林進二2, H.Y. Lee1, 門信一郎3, 水内 亨2, 長崎百伸2, 岡田浩之2, 南 貴司2,山本 聡2, 大島慎介5, 原田伴誉6, 香川 輔1, 向井清史1, L. Zang1, 荒井翔平1, 八代浩彰1,和多田泰士1, 和田善信1, 村上定義4, 中村祐司1, 花谷 清2, 木島 滋2, 佐野史道2
1

Graduate School of Energy Science, Kyoto University, Gokasho, Uji, 611-0011, Japan
京都大学大学院エネルギー科学研究科 〒611-0011 京都府宇治市五ヶ庄
2Institute of Advanced Energy, Kyoto University, Gokasho, Uji, 611-0011, Japan京都大学エネルギー理工学研究所 〒611-0011 京都府宇治市五ヶ庄3Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, 113-8656, Japan東京大学大学院工学系研究科 〒113-8656 東京都文京区本郷 7-3-1
4Graduate School of Engineering, Kyoto University, Yoshidahontyo, Sakyo-ku, 606-8501, Japan
京都大学大学院工学研究科 〒606-8501 京都府京都市左京区吉田本町
5Pioneering Research Unit for Next Generation, Kyoto University, Gokasho, Uji, 611-0011, Japan
京都大学次世代開拓ユニット 〒611-0011 京都府宇治市五ヶ庄
6
Undergraduate School of Electrical and Electronic, Faculty of Engineering, Kyoto University,
Yoshidahonmachi, Sakyo-ku, 606-8501, Japan
京都大学工学部電気電子工学科 〒606-8501 京都府京都市左京区吉田本町
This paper describes the measurement of the impurity ion temperature using Charge eXchange
Recombination Spectroscopy (CXRS) in Heliotron J. The measurable range of the CXRS system has been
extended from 0.37 < ρ < 0.79 to 0.07 < ρ < 0.94 with the spatial resolution ∆ρ ~ ±0.05 by installing newly
designed sightlines. The radial profile of the carbon ion temperature was measured in NBI plasmas. The
core ion temperature with CXRS is consistent with that measured with a charge exchange neutral particle
analyzer.

1. Introduction
In magnetically confined plasmas, themeasurement of the radial profile of the plasmapressure and the rotation velocities (vt and vp) is
indispensable not only for the heat or particle
transport analysis but also for the evaluation of
the radial electric field. The Charge eXchange
Recombination Spectroscopy (CXRS) has beenutilized for the measurements of the radial profileof the impurity ion temperature, density androtation velocity in high temperature fusion
plasmas [1]. The ion temperature and the rotation
velocity are evaluated from the Doppler
broadening and the Doppler shift of the lineemission
fromtheChargeeXchange
Recombination (CXR) reaction between the fully

ionized impurity ions (AZ+) and the neutral beam
particles (H0) as follows:

AZ + + H 0 → A(Z −1)+ (n = j → i ) + H + + hν (1).
In Heliotron J, a CXRS system has beendeveloped, and the ion temperature has beenmeasured in the range of 0.37 < ρ < 0.79 [2],where ρ is the normalized minor radius. We haverecently introduced a new objective opticalsystem in order to extend the measurable area.
We show initial results of the radial profile
measurements of the impurity ion temperature.
2. CXRS system in Heliotron JFigure 1 shows a schematic of the CXRS system

Fig.1. Schematic of CXRS system in Heliotron Jin Heliotron J, a helical-axis heliotron device with
an L=1/m=4 helical coil. Two sets of NBI (co andctr) for plasma heating are used as diagnostic beams.
An emission line of CVI (n=8→7, 529.05 nm) isused for the CXRS measurement since no strongline spectrum is observed near this wavelength andwe can use fiber bundles to guide the emission to aspectrometer. Two sets of the 14 sightlines are
newly installed for the beam-carbon CXR emission(#3.0 port) and the background emission (#7.0 port).
To optimize the spatial resolution of the CXR
measurement, the sightlines are chosen in parallelto the magnetic axis by taking into account theregion of the neutral beam passing. Figure 2 shows
the radial positions of the sightlines as a function of
the distance from the pivot point for this system.
This optimization enables us to measure the radial
profile of the CXR emission in the range of 0.07 <ρ < 0.94 with the spatial resolution of ∆ρ ~ ±0.05.
The plasma emission is led to a Czerny-Turnermonochromator whose focus length is 400 mm, F
number is 2.8 and grating is 2160 grooves/mm. ACCD camera (ANDOR DU-897, 512×512 pixels
and 16×16 µm) was installed to detect the spectral
and spatial profile of the CXR emission.
3. Experiments
Figure 3 shows an example of the radial profileof the carbon ion temperature and its time evolution.
The plasma was generated by ECH, and sustained

Fig.3. (a) radial profile of Ti, (b) time evolution of Ti atthree radial positions, (c) the stored energy Wp andthe line-averaged electron density

only by NBI from 170 ms to 270 ms. The NBI portthrough power was 920 kW in total. As shown inFig. 3(a), we obtained the ion temperature profile in
the range of 0.07 < ρ < 0.83. In the peripheral
region ρ > 0.83, however, the intensity of the CXR
emission was too low to estimate the iontemperature. The radial profile has a peaked shape,
and the temperature reached up to 200 eV atρ=0.07. Figure 3(b) shows the time evolution of thecarbon ion temperature at three radial positions.
The bulk (deuterium) ion temperature measured
with a Charge eXchange Neutral Particle Analyzer(CX-NPA) is also plotted in the figure. The centercarbon ion temperature agrees well with the bulk
ion temperature.
4. Summary
We measured the radial profile and time
evolution of the carbon ion temperature using theCXRS in Heliotron J. The radial profile measured
in the range of 0.07 < ρ < 0.83 has a peaked shape.
The ion temperature reaches up to 200 eV at thecore, and its time evolution agrees well with thebulk ion temperature measured with the CX-NPA.

Fig.2. Radial positions of channels

References[1] R.J. Fonck et al: Physical Review A, 29 (1984) 3288
[2] H.Y.Lee et al: 27th JSPS Annual meeting, Sapporo,
02P51 (2010)