title: X-ray tests of a two-dimensional stigmatic imaging scheme with variable magnifications.
abstract: A two-dimensional stigmatic x-ray imaging scheme, consisting of two spherically bent crystals, one concave and one convex, was recently proposed [M. Bitter et al., Rev. Sci. Instrum. 83, 10E527 (2012)]. The Bragg angles and the radii of curvature of the two crystals of this imaging scheme are matched to eliminate the astigmatism and to satisfy the Bragg condition across both crystal surfaces for a given x-ray energy. In this paper, we consider more general configurations of this imaging scheme, which allow us to vary the magnification for a given pair of crystals and x-ray energy. The stigmatic imaging scheme has been validated for the first time by imaging x-rays generated by a micro-focus x-ray source with source size of 8.4 μm validated by knife-edge measurements. Results are presented from imaging the tungsten Lα1 emission at 8.3976 keV, using a convex Si-422 crystal and a concave Si-533 crystal with 2d-spacings of 2.21707 Å and 1.65635 Å and radii of curvature of 500 ± 1 mm and 823 ± 1 mm, respectively, showing a spatial resolution of 54.9 μm. This imaging scheme is expected to be of interest for the two-dimensional imaging of laser produced plasmas.
authors.affiliation: Key Laboratory of Optoelectronic Technology and System of Ministry of Education, Chongqing University, Chongqing 400030, China.
authors.forename: J
authors.initials: J
authors.lastname: Lu
authors.affiliation: Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA.
authors.forename: M
authors.initials: M
authors.lastname: Bitter
authors.affiliation: Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA.
authors.forename: K W
authors.initials: KW
authors.lastname: Hill
authors.affiliation: Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA.
authors.forename: L F
authors.initials: LF
authors.lastname: Delgado-Aparicio
authors.affiliation: Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA.
authors.forename: P C
authors.initials: PC
authors.lastname: Efthimion
authors.affiliation: Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA.
authors.forename: N A
authors.initials: NA
authors.lastname: Pablant
authors.affiliation: Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
authors.forename: P
authors.initials: P
authors.lastname: Beiersdorfer
authors.affiliation: Inrad Optics, 181 Legrand Avenue, Northvale, New Jersey 07647, USA.
authors.forename: T A
authors.initials: TA
authors.lastname: Caughey
authors.affiliation: Inrad Optics, 181 Legrand Avenue, Northvale, New Jersey 07647, USA.
authors.forename: J
authors.initials: J
authors.lastname: Brunner