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Title: Observations of the ultraviolet and x-ray brightness profiles and cooling rates of Kr and Ar in magnetically confined fusion plasmas

Journal Article · · Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics
 [1];  [2];  [3];  [3];  [4];  [5];  [1];  [1];  [3];  [2]
  1. Plasma Spectroscopy Group, Department of Physics and Astronomy, The Johns Hopkins University, 34th and North Charles Streets, Baltimore, Maryland 21218 (United States)
  2. Lawrence Livermore National Laboratories, P.O. Box 808 L41, Livermore, California 94551 (United States)
  3. FTU, Associazione EURATOM ENEA sulla Fusione, Frascati (Roma), (Italy)
  4. Plasma Science and Fusion Center, Massachusetts Institute of Technology, 190 Albany Street, Cambridge, Massachusetts 02139 (United States)
  5. Institut National de la Recherche Scientifique and Centre Canadien de Fusion Magnetique, Varennes, (Canada)

The spatial brightness profiles of Ar and Kr ions have been measured during a set of experiments in which these gases were puffed into FTU (Frascati Tokamak Upgrade) and Alcator C-Mod tokamak plasmas. These profiles were measured by spatially scanning photometrically calibrated vuv and x-ray spectrometers covering 3 to 1700 Aa on a shot to shot basis. Several simulations of these profiles were performed using the multiple ionization state transport (MIST) code to validate the atomic physics rates used to determine the charge state distribution in the plasmas. A comparison of two sets of atomic physics rates was made. The chosen rates were the original rates in MIST and the more accurate ionization/recombination rate coefficients from the HULLAC atomic code and the current compilations by Mazzotta. The simulations with the more accurate rates could correctly predict the brightness profiles. The simulations with the older rates adequately predicted the Ar brightness profiles but did not accurately predict those of Kr. The inclusion of the excitation autoionization rates which were absent from the MIST code had the most profound effect on the simulated charge state distributions. (c) 2000 The American Physical Society.

OSTI ID:
20215740
Journal Information:
Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics, Vol. 61, Issue 3; Other Information: PBD: Mar 2000; ISSN 1063-651X
Country of Publication:
United States
Language:
English