Extreme ultraviolet study of tokamak plasmas using a time resolving spectrograph

Thesis/Dissertation · Sat Jan 01 04:00:00 EST 1983

OSTI ID:5928633

Bell, R E

A time-resolving spectrograph was developed to study the extreme ultraviolet emissions of tokamak plasmas. The spectrograph incorporates a detector system with 1024 detecting elements to record the entire spectrum in the 300-2200 A range every 3.7 ms. Multiple gratings are used to achieve either high dispersion, for good resolution, or low dispersion, for wide spectral coverage. The spectrograph was used to study the spectral emissions of two tokamaks: Alcator A at the Massachusetts Institute of Technology, Cambridge, Massachusetts, and TFR 600 of Association EURATOM-CEA, Fontenay-aux-Roses, France. The survey properties of the spectrograph were used to compare the impurity contents of these two machines, and to study conditions affecting the normal evolution of tokamak discharges. Impurity injection, involving the rapid vaporization of a metal film by a laser pulse, is a common technique used to study impurity behavior. The metals injected with this technique may alter the parameters of a plasma discharge. The spectral emissions of the TFR-600 tokamak were examined during a series of impurity injection experiments, under conditions of significant and negligible perturbation. Emissions from intrinsic impurities reveal that the conditions for impurity transport were altered in the perturbed case.

• Research Organization: Johns Hopkins Univ., Baltimore, MD (USA)
• OSTI ID: 5928633
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700102* -- Fusion Energy-- Plasma Research-- Diagnostics
CLOSED PLASMA DEVICES
ELECTROMAGNETIC RADIATION
EMISSION SPECTRA
EXTREME ULTRAVIOLET RADIATION
IMPURITIES
MEASURING INSTRUMENTS
PLASMA DIAGNOSTICS
RADIATIONS
SPECTRA
SPECTROMETERS
THERMONUCLEAR DEVICES
TOKAMAK DEVICES
ULTRAVIOLET RADIATION
ULTRAVIOLET SPECTROMETERS