E. Ishiyama

H. Totsuka

H. Toyama

K. Hanada

K. Shinohara

K. Yamagishi

N. Yamaguchi

S. Tyo

National Institute for Fusion Science (NIFS-Repository)

§20. Development of 3-dimensional Electron Temperature Measurement System with High Time Resolution Using Soft X-ray Spectroscopy with Multi-layer X-ray Mirror Toyarna,H. (Tokyo Univ.), Yarnaguchi,N. (Toyota Tech. Insti.), Tyo,S. (Tsukuba Univ.), Hanada,K. (Kyushu Univ.), Yarnagishi,K. (Tokyo Univ.), Shinohara,K. (JAERI), Totsuka,H. (Tokyo Univ.), Ishiyarna,E. (Tokyo Univ.) It is necessary to rneasure basic plasnm pararn-eters with high tin1e resolution in order to un-derstand plasrna physics. We have developed an electron ternperature rneasurernent system using soft X-ray spectroscopy. For spectroscopy we use a rnulti-layer X-ray rnirror. The electron ternpera-ture is rneasured frmn soft X-ray energy spectrurn. It is straightforward to rneasure the 3-dirnensional electron ternperature profile by tmnography. The tilne resolution of this rneasurernent systern is de-tennined by the band width of the detector and prearnplifier circuit, which can be up to approx-ilnately 1MHz. So we can measure the electron ternperature fluctuation. Figure 1 shows a schernatic view of the soft X-ray spectrorneter with rnulti-layer X-ray rnirror. The pin hole detennines the sight line of each de-tector. The Be filter rernoves low energy ernis-sion and suppresses total reflection. Soft X-ray ernission frorn the plasrna is spectrally resolved by Bragg reflection (2dsinB = n,\) at the surface of rnulti-layer X-ray rnirror, and detected by the PIN diode array. We use 924eV rv 1214eV in this systern as the energy range for spectroscopy based on reflec-tivity calibration of the rnulti-layer X-ray rnirror 0 (3% rv 25% at 330 eV rv 1250 eV, 2d = 66.7 A) and the sensitivity of the PIN diode (approxi-rnately 100% at 350eV rv 1250eV), plasrna pa-rameters, and the structures around the port in CHS. Band width of the detectors and preampli-fier circuit is 200kHz. This system is installed the on equatorial plain in CHS. We rneasure the electron ternperature with a space resolution of approxirnately 30 rnrn. After the measured soft X-ray intensity is corrected for reflectivity of the rnulti-layer X-ray rnirror, sensitivity of the PIN diodes, and transparency of the Be filter, we ob-tain the electron ternperature by spectrurn fitting. The result is cmnpared with the electron tern-perature rneasured by Thornson scattering as shown in Figure 2. The electron ternperature rneasured by soft X-ray spectroscopy with the rnulti-layer X-ray rnirror systern and the Thorn-son scattering systern coincides within error bars. pinhole and Be filter multi-layer X-ray mirror PIN diode array and preamplifier Fig. 1: Schernatic view of the soft X-ray spec-trmneter with rnulti-layer X-ray n1irror > ~ Q) :s -ro (i) 0. E Q) 1-c e 0 Q) w 3000 2500 2000 1500 1000 500 ··.\· J.J\ ; , N~tf~ :-~,.. ~ .. /~- '1 \ !. ' I" ' ~ \;of :1(\ x \Jr 0 ~--~----~--~----~--~ 20 30 40 50 60 Time [ms] 70 Fig. 2: Electron ternperature rneasured by soft X-ray spectroscopy using the rnulti-layer X-ray rnirror (dashed line) and by Thornson scattering (solid line with error bars) 141 

Development of 3-dimensional Electron Temperature Measurement System with High Time Resolution Using Soft X-ray Spectroscopy with Multi-layer X-ray Mirror

Development of 3-dimensional Electron Temperature Measurement System with High Time Resolution Using Soft X-ray Spectroscopy with Multi-layer X-ray Mirror

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