[Table of Contents]

Plasma and Fusion Research

Volume 2, S1073 (2007)

Regular Articles


New 20-Channel Diagnostic for Angle-Resolved Fast Particles Measurements in LHD
Evgeny A. VESHCHEV, Tetsuo OZAKI1), Pavel R. GONCHAROV1), Shigeru SUDO1) and LHD Experimental Group1)
Graduate University for Advanced Studies, Hayama 240-0193, Japan
1)
National Institute for Fusion Science, Toki 509-5292, Japan
(Received 4 December 2006 / Accepted 8 March 2007 / Published 20 November 2007)

Abstract

A new multi-channel diagnostic for fast particles has been developed and successfully tested on the Large Helical Device (LHD) during 2005-2006 experimental campaign. The number of simultaneously used channels was significantly improved from 2 to 20 channels and additional improvements for noise reduction have been made. Same time location of the diagnostic has been changed that allowed one to make measurements in a much wider range of pitch angles from perpendicular to tangential (90-160 degrees). All these improvements allow one to make time, energy, and angle-resolved measurements of charge exchange neutral particles in a single plasma discharge and to check the presence of fast particles loss-cones from LHD plasma in different heating regimes. This new diagnostic can be a very helpful and powerful tool in studying of fast particle distribution in such a complex helical plasma geometry like the one of LHD. Example data from plasma discharges are presented.


Keywords

fast particle measurement, ion distribution function, angle resolved measurement, fast ion confinement, neutral from plasma, ion kinetic

DOI: 10.1585/pfr.2.S1073


References

  • [1] P.R. Goncharov et al., Rev. Sci. Instrum. 77, 10F119 (2006).
  • [2] T. Ozaki et al., Rev. Sci. Instrum. 71, 2698 (2000).
  • [3] J.F. Lyon et al., Rev. Sci. Instrum. 74, 1873 (2003).
  • [4] E.A. Veshchev et al., Rev. Sci. Instrum. 77, 10F129 (2006).
  • [5] http://www.ird-inc.com/axuvarr.html
  • [6] J.F. Ziegler, Handbook of stopping cross-sections for energetic ions in all elements (Pergamon Press, New York, 1980).
  • [7] J.F. Ziegler, J.P. Biersack and U. Littmark, The stopping and range of ions in solids (Pergamon Press, New York, 1985).

This paper may be cited as follows:

Evgeny A. VESHCHEV, Tetsuo OZAKI, Pavel R. GONCHAROV, Shigeru SUDO and LHD Experimental Group, Plasma Fusion Res. 2, S1073 (2007).