Double-crystal x-ray spectroscopy at JET

Abstract

A double-crystal monochromator has been brought into operation at JET to measure absolute wavelengths and intensities of impurity spectral lines in the soft x-ray region from about 0.1 to 2.3 nm. It is capable of operating also during the deuterium-tritium (active) phase of JET because its detector is very effectively shielded against neutrons and hard x rays. The spectrometer has been swept over a wide wavelength range, around characteristic line groups as well as monochromatic line scans.