[Table of Contents]

Plasma and Fusion Research

Volume 2, S1096 (2007)

Regular Articles

Development of Neutral Molecular Beam Injector for Two-Dimensional Edge Density Measurement
H. TSUCHIYA, T. MORISAKI1), A. KOMORI1), Y. TAKAHASHI2), K. TOI1), H. ZUSHI3), O. MOTOJIMA1) and LHD Experimental Group1)
Graduate University for Advanced Studies, Toki 509-5292, Japan
1)
National Institute for Fusion Science, Toki 509-5292, Japan
2)
Department of Energy Engineering and Science, Nagoya University, Nagoya 464-8603, Japan
3)
Research Institute for Applied Mechanics, Kyushu University, Kasuga 816-8580, Japan
(Received 6 January 2007 / Accepted 26 April 2007 / Published 20 November 2007)

Abstract

A sheet-shaped thermal lithium beam probe has been developed for two-dimensional density measurements in the edge region of the torus plasma. For the production of an intense and uniform beam, the optimization of the nozzle shape and slit width of the beam injector has been performed. Beam density profiles at the observing region in the plasma were estimated with numerical calculations using a Monte Carlo technique for several kinds of nozzles and combinations with slits. Experiments on the test stand were also carried out, and pretty good agreement was found between numerical and experimental results. Based on these examination and optimization for the nozzle and slits, we have constructed a sheet-shaped beam injector for the large helical device. In spite of the long distance (about 3 m) from the injector, it is estimated that the thickness of the sheet-shaped beam is ∼90 mm (full width at half maximum).

Keywords

thermal lithium beam probe, LHD, sheet-shaped beam, neutral molecular beam injector, Mote Carlo technique, 2D measurements, edge plasma

DOI: 10.1585/pfr.2.S1096

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References

  • [1] S.I. Krasheninnikov, Phys. Rev. Lett. A 283, 368 (2001).
  • [2] J.A. Boedo et al., Phys. Plasmas 8, 4826 (2001).
  • [3] D.A. D'Ippolito et al., Phys. Plasma 10,4029 (2003).
  • [4] D.A. Russell et al., Phys. Rev. Lett. 93, 265001 (2004).
  • [5] K. Nakamura et al., Rev. Sci. Instrum. 76, 013504(2005).
  • [6] Y. Takahasi et al., J. Plasma Fusion Res. 1, 103 (2006).
  • [7] Y. Takahashi et al., J. Korean Phys. Soc. 49, S175 (2006).
  • [8] H. Tsuchiya et al., Rev. Sci. Instrum. 77, 10F526 (2006).
  • [9] T. Morisaki et al., Rev. Sci. Instrum. 74, 1865 (2003).

This paper may be cited as follows:

H. TSUCHIYA, T. MORISAKI, A. KOMORI, Y. TAKAHASHI, K. TOI, H. ZUSHI, O. MOTOJIMA and LHD Experimental Group, Plasma Fusion Res. 2, S1096 (2007).