Investigations on calibration sources for soft-x-ray plasma spectroscopy and impurity monitors

For absolute soft-x-ray line intensity measurements to deduce elemental concentrations and parameters of magnetically confined plasmas large-area x-ray sources are developed and investigated. These calibration sources use K, L, and M transitions in different elements and cover a wide photon energy (and wavelength) range. From the measured absolute line intensities of these sources the quantum efficiency values of numerous elements for K-, L-, and M-line emission per incident electron are deduced. They represent the basis of simple soft-x-ray monitors for impurities in fusion plasmas.