title: Focusing Properties of X-Ray Spectrometers with 2D-Curved Crystals for Extended X-Ray Sources of Hot Plasmas.
abstract: The focusing properties of very large (≈33 × 33 cm2) spherically and toroidally curved crystals with a radius of curvature of ≈10 m were determined numerically with an x-ray tracing code and are compared to those of cylindrically bent crystals. Large spherically and toroidally curved crystals are of interest for the diagnostic of future large tokamak fusion experiments and possibly for other extended x-ray sources. Compared with cylindrically bent crystals-which are now widely used for the plasma diagnostic in tokamak experiments, in particular, for Doppler-broadening measurements to determine the central ion temperature-2D-curved crystal spectrometers can provide a significant enhancement of the intensity due to the additional focusing of the sagittal rays.
authors.affiliation: Laboratory of X-Ray and VUV Spectroscopy, Racah Institute of Physics, Hebrew University, Jerusalem, Israel.
authors.forename: B S
authors.initials: BS
authors.lastname: Fraenkel
authors.forename: M
authors.initials: M
authors.lastname: Bitter
authors.forename: S
authors.initials: S
authors.lastname: von Goeler
authors.forename: K
authors.initials: K
authors.lastname: Hill