Light-impurity diagnostics in the T-4 tokamak

Journal Article · Sat Sep 01 04:00:00 EDT 1979 · Sov. J. Plasma Phys. (Engl. Transl.); (United States)

OSTI ID:5678246

Afrosimov, V V; Gordeev, Y S; Zinov'ev, A N; Korotkov, A A

A new diagnostic method has been used to determine the concentration of light impurities in the plasma of the T-4 tokamak. This method involves exciting additional emission through charge exchange of the impurity ions in a beam of fast hydrogen atoms injected into the plasma. The ion emission is analyzed both with and without the beam over the photon energy range 20--1000 eV with the help of a photoelectron spectrometer. The carbon concentration at the center of the plasma is 0.3--0.7% of the electron concentration under various discharge conditions. The results show that impurities do not build up at the center of the plasma. The effective time for the loss of carbon nuclei from the center of the plasma is estimated to be tau=20 +- 10 msec. The results from experiments with a graphite limiter in the tokamak show that this limiter holds promise for reducing the energy loss due to impurity emission and for reducing the effective charge of the plasma.

• Research Organization: A. F. Ioffe Physicotechnical Institute, Academy of Sciences of the USSR, Leningrad
• OSTI ID: 5678246
• Journal Information: Sov. J. Plasma Phys. (Engl. Transl.); (United States), Journal Name: Sov. J. Plasma Phys. (Engl. Transl.); (United States) Vol. 5:5; ISSN SJPPD
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700102* -- Fusion Energy-- Plasma Research-- Diagnostics
AUGER ELECTRON SPECTROSCOPY
BEAM INJECTION
CARBON
CHARGE EXCHANGE
CLOSED PLASMA DEVICES
ELECTRON SPECTROSCOPY
ELEMENTS
IMPURITIES
MEASURING INSTRUMENTS
NEUTRAL ATOM BEAM INJECTION
NONMETALS
PHOTOELECTRON SPECTROSCOPY
PLASMA DIAGNOSTICS
SPECTROMETERS
SPECTROSCOPY
THERMONUCLEAR DEVICES
TOKAMAK DEVICES
X-RAY SPECTROMETERS