23P027-P
Measurement of toroidal rotation velocity profile and calculation of external
momentum input by NBI in Heliotron J
ヘリオトロンJにおけるトロイダル回転速度分布計測ならびに	 NBI外部運動量入力計算	 
Hyunyong Lee1, Shinji Kobayashi2, Takayuki Minami1, Shinichiro Kado3, Tohru Mizuuchi2,
Kazunobu Nagasaki2, Hiroyuki Okada2, Takashi Minami2, Satoshi Yamamoto2,
Sadayoshi Murakami4, Shinsuke Ohshima5, Tomotaka Harada6, Tasuku Kagawa1, Kiyofumi Mukai1,Linge Zang1, Sigeru Konoshima2, Fumimichi Sano2
1
李	  炫庸 , 小林進二2，南	  貴之1，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，村上定義4，大島慎介5，原田伴誉6，香川	  輔1，向井清史1，Zang Linge1，
木島	  滋2，佐野史道2
1

Graduate School of Energy Science, Kyoto University, Uji, Kyoto, 611-0011, Japan
2
Institute of Advanced Energy, Kyoto University, Uji, Kyoto, 611-0011, Japan
3
Graduate School of Engineering, University of Tokyo, Bunkyo, Tokyo, 113-8656, Japan
4
Graduate School of Engineering, Kyoto University, Yoshida-honmachi, Kyoto, 606-8501, Japan
5
Pioneering Research Unit for Next Generation, Kyoto University, Uji, Kyoto, 611-0011, Japan
6
Faculty of Engineering, Kyoto University, Yoshida-honmachi, Kyoto, 606-8501, Japan1
京都大学エネルギー科学研究科 〒611-0011	  宇治市五ヶ庄
2
京都大学エネルギー理工学研究所	  〒611-0011	  宇治市五ヶ庄
3
東京大学工学系研究科	  〒113-8656	  東京市文京区本郷4
京都大学工学研究科	  〒611-0011	  京都市左京区吉田本町
5
京都大学次世代開拓ユニット	  〒611-0011	  宇治市五ヶ庄
6
京都大学工学部	  〒611-0011	  宇治市左京区吉田本町
This paper describes measurement of the toroidal rotation velocity profile in Heliotron J. The toroidal
rotation velocity is measured using CXRS and the external momentum input is calculated with the FIT
code. The measured toroidal rotation velocity profile is a center peaked one. In the plasma periphery, thetoroidal rotation, which is independent of the injected NB direction.

1. Introduction
Measurement of the toroidal plasma rotation (vϕ)
profile is important to investigate the momentum
transport in the magnetically confined plasma.
Neutral Beam Injection (NBI) is one of momentum
sources for the plasma. The injected neutral beam
drives vϕ of the plasma. It is important to estimate
the external momentum input by NBI and toinvestigate the effect of NBI on vϕ.
A Charge-eXchange Recombination Spectroscopy(CXRS) method [1] is a useful diagnostic to measure
the toroidal rotation velocity profile. This method is tomeasure a line emission from charge-exchange
recombination reactions between fully ionized
impurity ions (Az+) and energetic hydrogen atoms ofthe neutral beam (H0). We could estimate vϕ from theDoppler shift of the measured emission spectra. In
Heliotron J, we have installed a CXRS system tomeasure vϕ. Heliotron J is a helical-axis heliotron
device [2,3]. Two tangential neutral beam lines (BL1,BL2) are installed in Heliotron J. One is co direction(BL2) and the other is counter (ctr) injection (BL1) inthe normal direction of the magnetic field. Here, theco-direction is defined as the direction of plasma
current, which increases the rotational transform.
These beams are not only used for plasma heating but
also as diagnostic beams for CXRS.
In this paper, we describe measurement of thetoroidal rotation velocity profile and preliminary
comparison with the external momentum input byNBI profile in Heliotron J.

2.
Charge-exchange
Recombination
Spectroscopy System in Heliotron J
Figure 1 shows the schematic of CXRS system inHeliotron J. This system measures the CVI emission
line (n=7-8, 529.05 nm). We installed two sets ofoptical fiber (beam and background region), which areinstalled at two helically symmetric positions, toremove the cold component. Each optical set has 14sightlines, which are parallel to the magnetic axis toachieve high spatial resolution. We installed aCzerny-Turner monochromator, whose dispersion is0.0112 nm/pix at 529.05 nm. A camera with

Fig.1 Schematic view of CXRS system in Heliotron J.

back-illuminated charge coupled device is mounted on
the Czerny-Turner monochromator. The measurable
area in the plasma is 0.07 < ρ (=<r/a>) < 0.94 and thespatial resolution, Δρ, is about 0.05.

3. Experimental Result and PreliminaryComparison with the calculated external
momentum input by NBI
Figure 2 (a) and (b) show that the time evolutionof line averaged electron density and stored energy in
the NBI heating phase, respectively. In this phase,co- or ctr-NB, whose Pnbi were 600 kW and 450 kW,
is injected. The line averaged electron density is 1.2
× 1019 m-3 and stored energy is 1.1 kJ around 230 msin both cases. Figure 2 (c) and (d) shows that themeasured vϕ profile and the calculated external
momentum input (d(mnv)NB/dt), respectively.
The external momentum input is estimated using
the FIT code [4] based on the calculated fast ion
distribution by NBI with a three-dimensional Monte
Carlo simulation code including orbit loss and charge
exchange loss of fast ions. The external momentum
input is calculated as follow:[d(mnv)NB dt ](ρ) =€() , (1)Pnbi m f Z f v f H|| ( ρ) H(||+⊥ ) ( ρ) K ieE nbi

Here, Pnbi, H, Ki, Enbi are the port through power ofNB, the fast ion distribution, which is considered orbit
loss and charge exchange loss, the deposited fractionof initial fast-ion toroidal momentum by NBI [5] andthe acceleration voltage of NB, respectively.
In this experiment, the scanning of CXRS isperformed every 5 ms. The toroidal rotation velocity
profile is plotted 232.5 ms in the co-NBI plasma,227.5 ms in the ctr-NBI plasma. The external
momentum input is calculated at this time. The
measured toroidal rotation velocity profile, which iscenter peaked one, is qualitatively consistent with theshape to the calculated external momentum input
profile in the region of ρ < 0.6. In the plasma center(ρ = 0.07), the ratio between vϕ in the co- and ctr-NBI
plasma (vϕctr/vϕco) is about 0.7, which is close to theFig.2 Time evolution of (a) line averaged electron
density, (b) stored energy. (c) toroidal rotation
velocity profile, (d) calculated external momentum
input profile.

ratio of d(mnv)NB/dt, which is about 0.55. From thisresult, the external momentum input by NBI might
be one of dominant momentum sources. However,
the offset of toroidal rotation and the momentum
transport also should be investigated. On the otherhands, in spite of small d(mnv)NB/dt, vϕ of codirection, which is about 2~4 km/s and independentof the injected NB direction, is observed in theregion of ρ > 0.6. For the future work, the driving
mechanism of this rotation and the momentum
transport should be investigated.

4. Summary
We measured the toroidal rotation velocity using
CXRS and make a preliminary comparison with thecalculated the external momentum input by NBI with
the FIT code in Heliotron J. The measured toroidal
rotation velocity profile is qualitatively consistent
with the calculated NBI induced external momentum
input profile in the plasma core.
Acknowledgments
Authors are grateful for the great support ofHeliotron J technical staff. One of authors (H.Y.Lee)is grateful to Kyoto University GCOE program.
References[1] R. J. Fonck et al., Physical Review A 29 (1984) 6.
[2] M.Wakatani et al., Nucl. Fusion 40 (2000) 569. J[3] M.Yokoyama et al., Nucl. Fusion 40 (2000) 261.
[4] S.Murakami et al.,Trans. Fusion Tech.27(1995) 259.
[5] H.C.Howe, Physics models in the Toroidal Transport
Code, ORNL/TM-11521