Plasma and Fusion Research
Volume 9, 3402043 (2014)
Regular Articles
- Institute of Advanced Energy, Kyoto University, Kyoto 611-0011, Japan
- 1)
- National Institute for Fusion Science, Toki 509-5292, Japan
- 2)
- Graduate School of Energy Science, Kyoto University, Kyoto 611-0011, Japan
Abstract
A multichannel far-infrared (FIR) laser interferometer is being developed for the helical-axis heliotron device Heliotron J with asymmetrical poloidal cross-section to study high-density plasma. Due to the shape of the cross-section, a new density reconstruction method based on the regularization technique was investigated for obtaining the electron density profile from the line-integrated density. For this purpose, the regularization parameter was optimized and determined by the generalized cross-validation (GCV) function and singular value decomposition (SVD). The reconstruction results show that the reconstructed profiles can be improved by carefully considering the beam position arrangement. The optimum beam arrangement is discussed in detail.
Keywords
electron density reconstruction, regularization, GCV, SVD, FIR interferometer, Heliotron J
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References
- [1] T. Obiki, T. Mizuuchi, K. Nagasaki, H. Okada et al., Nucl. Fusion 41, 833 (2001).
- [2] N. Shi, S. Ohshima, K. Tanaka, T. Minami et al., submitted to Rev. Sci. Instrum.
- [3] G.H. Golub, M. Heath and G. Wahba, Technometrics 21, 215 (1979).
- [4] N. Iwama, H. Yoshida, H. Takimoto, Y. Shen et al., Appl. Phys. Lett. 54, 502 (1989).
- [5] Hyeon K. Park, Plasma Phys. Control. Fusion 31, 2035 (1989).
- [6] K. Tanaka, K. Kawahata, T. Tokuzawa, S. Okajima et al., Plasma Fusion Res. 3, 050 (2008).
- [7] T. Mizuuchi, F. Sano, K. Kondo et al., Fusion Sci. Technol. 50, 1 (2006).
- [8] T. Mizuuchi, K. Murai, S. Watanabe, S. Yamamoto et al., J. Nucl. Mater. 390-391, 428 (2009).
- [9] S.P. Hirshman and W.I. van Rjj, Comput. Phys. Commun. 43, 143 (1986).
This paper may be cited as follows:
Nan SHI, Shinsuke OHSHIMA, Kenji TANAKA, Takashi MINAMI, Kazunobu NAGASAKI, Satoshi YAMAMOTO, Yoshiaki OHTANI, Linge ZANG, Tohru MIZUUCHI, Hiroyuki OKADA, Shinichiro KADO, Shinji KOBAYASHI, Shigeru KONOSHIMA, Naoki KENMOCHI and Fumimichi SANO, Plasma Fusion Res. 9, 3402043 (2014).