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Development of a Laser Timing Controller for the High Time-Resolution Nd:YAG Thomson Scattering System in Heliotron J

Naoki KENMOCHI, Takashi MINAMI¹⁾, Shohei ARAI, Chihiro TAKAHASHI²⁾, Tohru MIZUUCHI¹⁾, Shinji KOBAYASHI¹⁾, Kazunobu NAGASAKI¹⁾, Yuji NAKAMURA, Hiroyuki OKADA¹⁾, Satoshi YAMAMOTO¹⁾, Shigeru KONOSHIMA¹⁾, Shinsuke OHSHIMA¹⁾, Kiyofumi MUKAI²⁾, Hyunyong LEE, Linge ZANG, Yoko NAGAE, Mengyu SHA, Yoshiaki OHTANI, Keijun KASAJIMA, Tomotaka HARADA, Hiroto WATADA, Hirofumi FUKUSHIMA, Yukinobu SUGIMOTO, Yuichi NAKAMURA, Kohei HASHIMOTO and Fumimichi SANO¹⁾

Graduate School of Energy Science, Kyoto University, Gokasho, Uji 611-0011, Japan

1)

Institute of Advanced Energy, Kyoto University, Gokasho, Uji 611-0011, Japan

2)

National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292, Japan

(Received 7 December 2012 / Accepted 19 June 2013 / Published 26 September 2013)

Abstract

A new laser timing controller for the high time-resolution Nd:YAG Thomson scattering system with two Nd:YAG lasers has been developed to study improved confinement physics in Heliotron J. A PIC-based timing controller synchronizes the timings of laser oscillations with plasma discharges and enables the measurement of plasma profiles with a precision of <1 μs. The timing controller is used for the “soft start” of the system, which protects the optical components against initial unstable laser oscillations. The timing controller is designed to precisely control the delay time of the laser pulse from one laser to another, and to investigate the profile change of electron temperature and density within a short time span (> 80 ns), which is crucial for transport physics studies including spontaneous transitions.

Copyright (c) 2013 The Japan Society of Plasma Science and Nuclear Fusion Research

Keywords

Heliotron J, plasma diagnostic, Nd:YAG laser Thomson scattering measurement, electron temperature and density measurement, improved confinement

DOI: 10.1585/pfr.8.2402117

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References

• [1] F. Sano et al., Nucl. Fusion 45, 1557 (2005).
• [2] T. Minami et al., Rev. Sci. Instrum. 81, 10D532 (2010).
• [3] T. Minami et al., Plasma Fusion Res. 1, 021 (2006).
• [4] C.M. Greenfield et al., Rev. Sci. Instrum. 61, 3286 (1990).
• [5] R.E. Stockdale et al., Rev. Sci. Instrum. 66, 490 (1995).
• [6] G. Naylor, Rev. Sci. Instrum. 81, 10E110 (2010).
• [7] PIC18F2455/2550/4455/4550 Data Sheet. Microchip Technology Inc.

This paper may be cited as follows:

Naoki KENMOCHI, Takashi MINAMI, Shohei ARAI, Chihiro TAKAHASHI, Tohru MIZUUCHI, Shinji KOBAYASHI, Kazunobu NAGASAKI, Yuji NAKAMURA, Hiroyuki OKADA, Satoshi YAMAMOTO, Shigeru KONOSHIMA, Shinsuke OHSHIMA, Kiyofumi MUKAI, Hyunyong LEE, Linge ZANG, Yoko NAGAE, Mengyu SHA, Yoshiaki OHTANI, Keijun KASAJIMA, Tomotaka HARADA, Hiroto WATADA, Hirofumi FUKUSHIMA, Yukinobu SUGIMOTO, Yuichi NAKAMURA, Kohei HASHIMOTO and Fumimichi SANO, Plasma Fusion Res. 8, 2402117 (2013).