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laser for collective Thomson scattering diagnostic of 
particles in burning plasmasKondoh, Takashi; Hayashi, Toshimitsu; Kawano, Yasunori; Kusama, Yoshinori; Sugie, Tatsuo; Miura, Yukitoshi; Koseki, Ryoji*; Kawahara, Yoshihiro*
Review of Scientific Instruments, 77(10), p.10E505_1 - 10E505_3, 2006/10
Times Cited Count：6 Percentile：33.37(Instruments & Instrumentation)A collective Thomson scattering (CTS) technique based on a pulsed CO laser is being developed in order to establish a diagnostic method of confined -particles in burning plasmas. In International Thermonuclear Experimental Reactor (ITER), measurement of velocity and spatial distributions of confined -particles requires temporal resolution of 0.1 s and spatial resolution of a/10, where a is plasma minor radius. A new laser system (Energy 
10J, repetition 10Hz) has been developed based on a commercially available laser (Shibuya Kogyo Co., Ltd, SEL4000) to meet the requirement of temporal resolution of ITER and to improve a signal-to-noise ratio. The laser has unstable resonator with a cavity length of 4 m and discharge electrodes with heat exchanger of laser gas for high-repetition operation. Proof-of-principle test of the CTS technique will be performed with the new laser system on JT-60U (JAEA Tokamak 60 - Upgrade). This work was supported by Grant-in-Aid for Scientific Research on Priority Areas "Advanced Diagnostics for Burning Plasmas" from Ministry of Education, Culture, Sports, Science and Technology, No.16082210.
laser calibration of the infrared imaging video bolometer for the JT-60U tokamakParchamy, H.*; Peterson, B. J.*; Konoshima, Shigeru; Hayashi, Hiromi*; Seo, D. C.*; Ashikawa, Naoko*; JT-60U Team
Review of Scientific Instruments, 77(10), p.10E515_1 - 10E515_4, 2006/10
Times Cited Count：14 Percentile：56.02(Instruments & Instrumentation)no abstracts in English
Shinohara, Koji; Isobe, Mitsutaka*; Darrow, D. S.*
Review of Scientific Instruments, 77(10), p.10E521_1 - 10E521_4, 2006/10
Times Cited Count：5 Percentile：29.24(Instruments & Instrumentation)A scintillator probe can measure the temporal evolution of both the gyro-radius and the pitch angle of the escaping ions with relatively large energy. On this system, the time resolution of the 2D measurement is determined by a framing rate of the camera. The framing rate of the old camera was 60Hz, thus the time resolution was about 17 ms. Our interest is to understand the energetic ion transport in fast events such as a bursting Alfv
n eigenmode. The typical time scale of these event interested is less than a few ms. The time resolution of the old camera was not enough for this purpose. The FASTCAM ultima II, which is a product of Photron Co., is an image-intensified high-speed video camera system with the ability to record up to 13,500 frames per second. By replacing the old camera with this ultima II, the temporal resolution was improved from about 17 ms to 0.075 ms. We have successfully installed the fast camera and captured some fast events caused by MHDs, which was not observed by the old camera. Here, we will present the specification of this system and the preliminary results using this fast camera.
Suzuki, Takahiro; Fujita, Takaaki; Oyama, Naoyuki; Isayama, Akihiko; Matsunaga, Go; Oikawa, Toshihiro; Asakura, Nobuyuki; Takechi, Manabu
Review of Scientific Instruments, 77(10), p.10E914_1 - 10E914_4, 2006/10
Times Cited Count：7 Percentile：37.04(Instruments & Instrumentation)In JT-60U, we measure temporal evolution (100Hz) of the pitch angles of the magnetic field, using a 30 channel motional Stark effect (MSE) diagnostic with photo-elastic modulators (PEMs). This year, we started acquiring the signal intensity of photo-multipliers (PMs) at 0.5-1MHz sampling for fluctuation profile measurement. Response of the PM (180kHz/-3dB) limits the temporal resolution. The system works as the MSE and the beam emission spectroscopy (BES) diagnostic. Coupling between the MSE and BES signals can provide magnetic fluctuation. Here we report on results in spatially resolved electron density (ne) fluctuation profile measurement in various operation regimes. In the core plasma, ne fluctuation induced by rotating tearing mode islands was observed. Phase of the fluctuations are inverted between higher and lower magnetic field sides, which is consistent with an electron cyclotron emission (ECE) measurement. In the scrape-off layer of an ELMy 
-mode plasma, outward propagation of strong emission coincides with ELM crash was also observed. The propagation velocity is about 6km/s along the MSE measurement points, where distance between adjacent channels is 6-7cm in the major radius direction. Detailed description of the optics and the system will be presented.
Hatae, Takaki; Naito, Osamu; Nakatsuka, Masahiro*; Yoshida, Hidetsugu*
Review of Scientific Instruments, 77(10), p.10E508_1 - 10E508_6, 2006/10
Times Cited Count：30 Percentile：76.24(Instruments & Instrumentation)no abstracts in English
