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Current issue Ukr. J. Phys. 2016, Vol. 61, N 9, p.806-811
Dreval M.B.1, Turianska O.V.2
1 National Science Center “Kharkov Institute of Physics and Technology”,
Nat. Acad. of Sci. of Ukraine
(1, Akademichna Str., Kahrkiv 61108, Ukraine)
2 V.N. Karazin Kharkiv National University
(4, Svobody Sq., Kharkiv 61022, Ukraine)
Concerning Space Distribution of the Soft X-Ray Emissivity in the U-3M Torsatron
Section: Plasmas and Gases
Original Author's Text: English
Abstract: A miniature pinhole camera array has been installed on the U-3M torsatron for spatially re-solved measurements of soft X-ray plasma emission along 20 lines of sights. The recent line-integrated SXR emission data provide important information about the U-3M plasma confine-ment. The local SXR emissivity distribution in the poloidal cross-section “A-A” is calculated numerically on the base of experimental data. The U-3M magnetic surfaces have been approx-imated as a set of normalized plasma radius data in the grid covering this cross-section. The local SXR emissivity is determined as a function of the normalized radius. The line-integrated SXR emission is calculated for every viewing area of each SXR channel on the base of this local emissivity in the real geometry of the SXR diagnostics. A fitting of the calculated line-integrated SXR emission profiles to the experimental profiles shows that the radial profiles of local SXR emissivity are quite narrow, with strong gradient in the central plasma part. The SXR emissivity profiles are quite different from the parabolic form.
Key words: U-3M, SXR, tomography.
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