INTERPRETATION OF CAPILLARY GENERATED SPATIAL AND ANGULAR-DISTRIBUTIONS OF X-RAYS - THEORETICAL MODELING AND EXPERIMENTAL-VERIFICATION USING THE EUROPEAN SYNCHROTRON-RADIATION FACILITY OPTICAL BEAM LINE

Using a detailed ray-tracing code for capillary optics, interpretation is given for parallel bore hole and tapered capillary generated far-f ield images. These images can be used to indicate the presence of vari ous types of surface imperfections (i.e., surface roughness or wavines s) or shape distortions of the optical device. The capillary output pa tterns were recorded at the optical beam line of the European Synchrot ron Radiation Facility by using a monochromatic, highly parallel incid ent synchrotron beam. Capillaries of various dimensions were studied, with inlet diameters in the range of 30-70 mu m, outlet diameters of 2 2-42 mu m and capillary length values ranging from 10 to 23 cm. mm, Th e far-field images were taken at a distance of 10-11 cm from the capil lary exit using a high resolution charge coupled device camera. By com parisons of simulated and experimental capillary output patterns, the effects of surface roughness/waviness, as well as axial distortions ar e studied with respect to the angular distribution of the generated ca pillary beam. (C) 1998 American Institute of Physics. [S0034-6748(98)0 4509-2].