Measurement of Spurious Impurity Concentrations in ASDEX Upgrade by X-Ray Spectroscopy
A two channel multi crystal spectrometer of Bragg geometry was used for measurements of absolute photon fluxes of ASDEX Upgrade plasmas in the wavelength range from 0.5 up to 26 . The calibration of the spectrometer was done by an ab initio calculation using the absolute reflection data from literature of 4 crystals. The calibration was validated by direct comparison with other absolute calibrated diagnostics at the ASDEX Upgrade as well as by using the impurity transport code STRAHL. The absolute impurity concentrations of elements from N up to Cu have been extracted. O and F appear to be main impurity components after C, which is routinely measured by an independent diagnostic. Other impurities either have never been seen or (like Fe and Cu) appear only sporadically and normally do not contribute significantly to plasma radiation in soft x-ray range.
Bibliographic Reference: Report: IPP 10/13 EN (2000) 29 pp.
Availability: Available from the Max Planck Institute f³r Plasmaphysik (DE)
Record Number: 200012092 / Last updated on: 2000-06-23
Original language: en
Available languages: en