X-ray Optics with Small Vertical Divergence and Horizontal Focusing Foran X-ray Standing-wave Measurement

Abstract

An x-ray optics was proposed for dynamical diffraction measurements of a non-ideal crystal. It was composed of a pair of channel-cut Si (004) crystals and a one-dimensional focusing lens system. Vertical angular divergence values were measured as FWHM's of ca. 1.3 arc secs for an incident photon energy of 12.4 keV during a rocking scan around the analyzer sapphire 0006 reflection when the second channel-cut crystal was fixed at five deviation angles. The experimental angular resolution deconvoluted is about 1.3 arc secs at the deviation angle of ca. 0.7 arc sec. A typical photon flux was around 10⁹ photons /s as a peak value of the rocking scan for an incident slit of 0.2 x 0.1mm. The horizontal beam size measured at the focal distance of ca. 200 mm was 4.3 μm.