DocumentCode :
1893845
Title :
Low-Z impurity visible line radiations in the IR-T1 tokamak
Author :
Ghorannevis, M. ; Salami, M.R. ; Masnavi, Majid
Author_Institution :
Plasma Phys. Res. Center, IAU, Tehran, Iran
fYear :
1997
fDate :
19-22 May 1997
Firstpage :
245
Abstract :
Summary form only given, as follows. Impurities emitted from the limiter and/or wall by the bombardment of plasma and hot neutral particles play an important role in tokamak discharges. The spectroscopic measurements of line emission are commonly used to evaluate the concentration, influx rate and power radiated by low-Z impurities. During the ohmic heating discharge, the quasi-stationary profiles of the carbon (C III) and oxygen (O II, O III) impurity ionization stages in IR-T1 tokamak (R=45 cm, a=12.4 cm, 1/sub p/=20-40. KA, B/sub t/=0.6-0.9 tesla, T/sub d/=20-25 ms) were determined by monitoring visible line emissions with a single-channel visible (or near ultraviolet) monochromator with 0.6 cm space resolution, in which there is a two-lens image system in front of the spectrometer entrance slit and a multichannel optical fiber attached to its exit slit. The numerical analysis was done by a set of coupled continuity equations in cylindrical coordinates with ionization and recombination coefficients given by Lotz semi-empirical formula and by Kramer formula, respectively. The solar corona model was used to relate the stage densities and line emissivities. We found that the majority of the oxygen and carbon ions are He-like ones.
Keywords :
plasma diagnostics; plasma impurities; plasma ohmic heating; plasma toroidal confinement; solar corona; 0.6 to 0.9 tesla; 20 to 40 kA; IR-T1 tokamak; Kramer formula; Lotz semi-empirical formula; concentration; coupled continuity equations; cylindrical coordinates; exit slit; hot neutral particles; impurity ionization; influx rate; ionization coefficients; line emission; low-Z impurity visible line radiations; multichannel optical fiber; near ultraviolet monochromator; numerical analysis; ohmic heating discharge; plasma; power radiation; quasistationary profiles; recombination coefficients; solar corona model; spectrometer entrance slit; spectroscopic measurements; tokamak discharges; two-lens image system; visible line emissions; visible monochromator; Carbon dioxide; Heating; Image resolution; Impurities; Ionization; Monitoring; Plasma measurements; Power measurement; Spectroscopy; Tokamaks;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Plasma Science, 1997. IEEE Conference Record - Abstracts., 1997 IEEE International Conference on
Conference_Location :
San Diego, CA, USA
ISSN :
0730-9244
Print_ISBN :
0-7803-3990-8
Type :
conf
DOI :
10.1109/PLASMA.1997.604983
Filename :
604983
Link To Document :
بازگشت