THE JET HIGH RESOLUTION BENT CRYSTAL SPECTROMETER
The bent crystal spectrometer of the Johann type, built for the JET tokamak, is described. The high resolution instrument is characterised by a very long focal length, allowing the crystal and the position sensitive detector to be placed outside the JET torus hall, in order to keep the background radiation induced noise to an acceptable level. Through the analysis of the profiles of lines emitted by impurities, the ion temperature is measured. By analysing different lines present in the spectra and their wavelengths, relevant information is obtained about other plasma parameters, such as the electron temperature, the impurity ionisation equilibrium and concentration, and the plasma toroidal velocity. Examples of the results obtained during the first year of operation of this instrument are also illustrated.
Bibliographic Reference: REPORT: RT/FUS/87/38 EN (1989)
Record Number: 1989128057700 / Last updated on: 1990-11-09
Available languages: en