title: X-ray imaging crystal spectroscopy for use in plasma transport research.
abstract: This research describes advancements in the spectral analysis and error propagation techniques associated with x-ray imaging crystal spectroscopy (XICS) that have enabled this diagnostic to be used to accurately constrain particle, momentum, and heat transport studies in a tokamak for the first time. Doppler tomography techniques have been extended to include propagation of statistical uncertainty due to photon noise, the effect of non-uniform instrumental broadening as well as flux surface variations in impurity density. These methods have been deployed as a suite of modeling and analysis tools, written in interactive data language (IDL) and designed for general use on tokamaks. Its application to the Alcator C-Mod XICS is discussed, along with novel spectral and spatial calibration techniques. Example ion temperature and radial electric field profiles from recent I-mode plasmas are shown, and the impact of poloidally asymmetric impurity density and natural line broadening is discussed in the context of the planned ITER x-ray crystal spectrometer.
authors.affiliation: MIT-Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA.
authors.forename: M L
authors.initials: ML
authors.lastname: Reinke
authors.forename: Y A
authors.initials: YA
authors.lastname: Podpaly
authors.forename: M
authors.initials: M
authors.lastname: Bitter
authors.forename: I H
authors.initials: IH
authors.lastname: Hutchinson
authors.forename: J E
authors.initials: JE
authors.lastname: Rice
authors.forename: L
authors.initials: L
authors.lastname: Delgado-Aparicio
authors.forename: C
authors.initials: C
authors.lastname: Gao
authors.forename: M
authors.initials: M
authors.lastname: Greenwald
authors.forename: K
authors.initials: K
authors.lastname: Hill
authors.forename: N T
authors.initials: NT
authors.lastname: Howard
authors.forename: A
authors.initials: A
authors.lastname: Hubbard
authors.forename: J W
authors.initials: JW
authors.lastname: Hughes
authors.forename: N
authors.initials: N
authors.lastname: Pablant
authors.forename: A E
authors.initials: AE
authors.lastname: White
authors.forename: S M
authors.initials: SM
authors.lastname: Wolfe