Plasma and Fusion Research

Volume 3, S1086 (2008)

Regular Articles


Determination of Iron Density at the Plasma Center Using Radial Profile of FeKα Lines in LHD
Sadatsugu MUTO, Shigeru MORITA and LHD Experimental Group
National Institute for Fusion Science, Toki 509-5292, Japan
(Received 24 November 2007 / Accepted 8 March 2008 / Published 5 August 2008)

Abstract

Radial profiles of Kα X-ray spectra of metallic impurities have been measured using an assembly of soft X-ray pulse-height analyzers in Large Helical Device. The assembly is quipped with a radial scanning system, which gives us detailed profile information, especially in long pulse discharges. The local emissivity profiles of the Fe-Kα X-ray spectra have been quantitatively obtained by an Abel inversion technique. The density profile of the iron impurity in each charge state is analyzed using the energy shift profiles of the Fe-Kα spectra with the help of an impurity code analysis. As an example of the present method, the iron density of 1.2× 109 cm-3 in the plasma center is obtained at the line-averaged electron density of 2.6× 1013 cm-3.


Keywords

pulse height analyzer, iron, chromium, titanium, Large Helical Device

DOI: 10.1585/pfr.3.S1086


References

  • [1] S. Muto et al., Rev. Sci. Instrum. 74, 1993 (2003).
  • [2] M. Bitter et al., Phys. Rev. Lett. 43, 129 (1979).
  • [3] S. Muto et al., J. Plasma Fus. Res. SERIES8, to be published.
  • [4] S. Muto et. al., Fusion Eng. Des. 34-35, 205 (1997).
  • [5] S. Muto et al., Rev. Sci. Instrum. 72, 1206 (2001).
  • [6] M. Bitter et al., Phys. Scripta T37, 66 (1991).
  • [7] F. Bely-Dubau et al., Phys. Scripta T7, 34 (1984).
  • [8] V.L. Jacobs et al., Phys. Rev. A 39, 2441 (1989).
  • [9] J.L. Schwob et al., Space Science Rev. 13, 589 (1972).
  • [10] H. Nozato, S. Morita et al., Phys. Plasmas 11, 1920 (2004).
  • [11] H. Nozato, S. Morita et al., Phys. Plasmas 13, 092502 (2006).

This paper may be cited as follows:

Sadatsugu MUTO, Shigeru MORITA and LHD Experimental Group, Plasma Fusion Res. 3, S1086 (2008).