REFRACTION PHENOMENA IN X-RAY-SCATTERING EXPERIMENTS PERFORMED WITH ANARROW COLLIMATOR APERTURE

The observations of refraction phenomena in X-ray scattering experimen ts performed with a narrow collimator aperture are reported. Experimen tal observations of complicated intensity profiles obtained using diff erent narrow collimator slit sizes at eight radiation energies, from 6 .93 keV to 24.95 keV, showed an unavoidable contribution of the refrac tion effect in the collimator slit edges. It is demonstrated that a di fferent shape of the collimator slit produces different scattered inte nsity profiles that can make a parasitic contribution to the radiation wave front, An experimental technique is suggested for the direct mea surement of the refractive index of materials with high-energy X-rays. (C) 1998 Elsevier Science B.V. All rights reserved.