title: Calibration of a two-color soft x-ray diagnostic for electron temperature measurement.
abstract: The two-color soft x-ray (SXR) tomography diagnostic on the Madison Symmetric Torus is capable of making electron temperature measurements via the double-filter technique; however, there has been a 15% systematic discrepancy between the SXR double-filter (SXRDF) temperature and Thomson scattering (TS) temperature. Here we discuss calibration of the Be filters used in the SXRDFmeasurement using empirical measurements of the transmission function versus energy at the BESSY II electron storage ring, electron microprobe analysis of filter contaminants, and measurement of the effective density. The calibration does not account for the TS and SXRDFdiscrepancy, and evidence from experiments indicates that this discrepancy is due to physics missing from the SXRDFanalysis rather than instrumentation effects.
authors.affiliation: University of Wisconsin - Madison, Madison, Wisconsin 53703, USA.
authors.forename: L M
authors.initials: LM
authors.lastname: Reusch
authors.affiliation: University of Wisconsin - Madison, Madison, Wisconsin 53703, USA.
authors.forename: D J
authors.initials: DJ
authors.lastname: Den Hartog
authors.affiliation: Consorzio RFX, Padova, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Franz
authors.affiliation: University of Wisconsin - Madison, Madison, Wisconsin 53703, USA.
authors.forename: J
authors.initials: J
authors.lastname: Goetz
authors.affiliation: University of Wisconsin - Madison, Madison, Wisconsin 53703, USA.
authors.forename: M B
authors.initials: MB
authors.lastname: McGarry
authors.affiliation: University of Wisconsin - Madison, Madison, Wisconsin 53703, USA.
authors.forename: H D
authors.initials: HD
authors.lastname: Stephens