Plasma and Fusion Research

Volume 3, S1084 (2008)

Regular Articles

Helium Ion Observation during 3rd Harmonic Ion Cyclotron Heating in Large Helical Device
Tetsuo OZAKI, Pavel R. GONCHAROV, Evgeny A. VESHCHEV1), Shigeru SUDO, Tetsuo SEKI, Hirofumi KASAHARA, Yuichi TAKASE2), Takuya OHSAKO2), High-Energy Particle Group and LHD Experimental Group
National Institute for Fusion Science, 322-6 Oroshi, Toki Gifu 509-5292, Japan
1)
Graduate University for Advanced Studies, Hayama, Kanagawa 240-0193, Japan
2)
Department of Complexity Science and Engineering, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba 277-8561, Japan
(Received 24 October 2007 / Accepted 24 March 2008 / Published 1 August 2008)

Abstract

In higher harmonic ion cyclotron resonance heating using the fast wave, a helium resonance layer appears near the plasma core. It is very important to detect the helium ions to investigate the confinement of α particles, which are produced by a nuclear reaction in ITER or a fusion reactor. In Large Helical Device (LHD), we attempt to observe the charge-exchange helium particles using a compact neutral particle analyzer (CNPA). Helium acceleration below 5 keV can be confirmed by comparing the signal ratio of helium in adjusted plate voltages of the CNPA to that of hydrogen. Successful helium measurement in LHD will lead to the development of α particle measurement.

Keywords

ICH, 3rd harmonic, helium, α particle, CNPA, LHD, plate voltage, resonance

DOI: 10.1585/pfr.3.S1084

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References

  • [1] L. Chen, Phys. Plasmas 1, 1519 (1994).
  • [2] O. Motojima et al., Fusion Eng. Des. 20, 3 (1993).
  • [3] Y. Kubota et al., , J. Nucl. Mater., 313-316, 239 (2003).
  • [4] T. Mutoh et al., Phys. Rev. Lett. 85, 4530 (2000).
  • [5] H.Kasahara et al., 5th Asia Plasma Fusion Association, Jeju, Korea, Aug., (2005).
  • [6] T. Seki, private communication.
  • [7] T. Ozaki et al., Rev. Sci. Instrum. 77, 10E917 (2006).
  • [8] T. Ozaki et al., JPFR Series, (to be published).
  • [9] T. Ozaki et al., proc. of Burning Plasma Diagnostics in Varenna (2007) (to be published).
  • [10] Y. Takase, private communication.

This paper may be cited as follows:

Tetsuo OZAKI, Pavel R. GONCHAROV, Evgeny A. VESHCHEV, Shigeru SUDO, Tetsuo SEKI, Hirofumi KASAHARA, Yuichi TAKASE, Takuya OHSAKO, High-Energy Particle Group and LHD Experimental Group, Plasma Fusion Res. 3, S1084 (2008).