Plasma and Fusion Research
Volume 5, S1021 (2010)
Regular Articles
- Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292, Gifu, Japan
- 1)
- National Institute for Fusion Science, Toki 509-5292, Gifu, Japan
Abstract
Visible bremsstrahlung emission has been measured along the vertical direction of a horizontally elongated plasma cross section in a range of −0.6 m ≤ z ≤ 0.0 m from an inwardly shifted (Rax ≤ 3.6 m) configuration by means of an optimized Czerny-Turner spectrometer installed on the Large Helical Device. Chord-integrated bremsstrahlung intensity profiles have been observed in discharges having no asymmetric strong edge bremsstrahlung emission originating in the ergodic layer. Radial bremsstrahlung emission profiles are obtained from the chord-integrated profiles based on an Abel inversion method. Zeff profiles are thus analyzed for peaked, flat, and hollow density profiles, which are measured with a Thomson scattering diagnostic, as the first trial of the analysis. As a result, a flat Zeff profile is obtained for all different density profiles with values of 1 < Zeff ≤ 2. This indicates that the partial impurity pressure is essentially constant against the plasma radius.
Keywords
Zeff profile, visible bremsstrahlung, density profile
Full Text
References
- [1] D. P. Schissel et al., Phys. Fluids 31, 3738 (1988).
- [2] S. Morita, M. Goto et al., Physica Scripta T91, 48 (2001).
- [3] H. Y. Zhou, S. Morita, M. Goto and M. B. Chowdhuri, Rev. Sci. Instrum. 79, 10F536 (2008).
- [4] H. Nozato, S. Morita and M. Goto, J. Plasma Fusion Res. 5, 442 (2002).
- [5] K. Narihara et al., Rev. Sci. Instrum. 72, 1122 (2001).
- [6] S. P. Hirshman, W. I. van Rij and P. Merkel, Comput. Phys. Commun. 43, 143 (1986).
This paper may be cited as follows:
Hangyu ZHOU, Shigeru MORITA, Motoshi GOTO, Kazumichi NARIHARA and Ichihiro YAMADA, Plasma Fusion Res. 5, S1021 (2010).