title: Divertor electron temperature and impurity diffusion measurements with a spectrally resolved imaging radiometer.
abstract: A divertor imaging radiometer (DIR) diagnostic is being studied to measure spatially and spectrally resolved radiated power P(rad)(λ) in the tokamak divertor. A dual transmission grating design, with extreme ultraviolet (~20-200 Å) and vacuum ultraviolet (~200-2000 Å) gratings placed side-by-side, can produce coarse spectral resolution over a broad wavelength range covering emission from impurities over a wide temperature range. The DIR can thus be used to evaluate the separate P(rad) contributions from different ion species and charge states. Additionally, synthetic spectra from divertor simulations can be fit to P(rad)(λ) measurements, providing a powerful code validation tool that can also be used to estimate electron divertor temperature and impurity transport.
authors.affiliation: Johns Hopkins University, Baltimore, Maryland 21218, USA. dclayton@pppl.gov
authors.forename: D J
authors.initials: DJ
authors.lastname: Clayton
authors.forename: M A
authors.initials: MA
authors.lastname: Jaworski
authors.forename: D
authors.initials: D
authors.lastname: Kumar
authors.forename: D
authors.initials: D
authors.lastname: Stutman
authors.forename: M
authors.initials: M
authors.lastname: Finkenthal
authors.forename: K
authors.initials: K
authors.lastname: Tritz