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Third generation synchrotron light sources present new challenges to x-ray optics calculations. Due to the high brilliance (thus small dimensions) of the source and the long optical paths, the transverse coherence lengths are quite nonnegligible, often of order of hundreds of microns. In such situation beam propagation calculations based on purely geometrical optics may yield large errors and a more complete wave treatment is needed. This is especially true for beam defining apertures. The purpose of this paper is to present a calculational approach which, utilizing a 'variance matrix' representation of the beam allows to evaluate the wave propagation along an optical system and through arbitrary apertures, in a straightforward manner. In addition the notoriously thorny problem of partial coherence is adequately dealt with and the transition from wave optics to ray optics obtains in a smooth and seamless fashion.

A detailed thermal deformation and slope-error analysis is performed on an indirectly-cooled design of a high-heat-load vertical-focusing mirror.THe cooling of the mirror is through copper plates inserted into two grooves along the sides of the mirror. The contact between the mirror and the copper plate is through a gallium-indium eutectic bath in the groove. This configuration provides efficient thermal contact between the mirror substrate and the cooling block without applying stress to the mirror from the cooling block. This mirror will be used at the Advanced Photon Source Sector-15 ChemMatCARS undulator beamline for vertical focusing. It will be exposed to white beam with a heat load of about 1.1 kw.

A series of experimental measurements was conducted for the characterization of a transmission circular zone plate. The zone plate (ZP), with a primary focal length of 40 cm for 8 keV photons, was illuminated by monochromatized synchrotron x rays. Focusing efficiency of the ZP was measured as a function of x-ray energy between 5 - 1 keV, from which the ZP thickness was determined. Focal spot sizes at the first, second, and third order focus were measured, and they agreed very well with the calculated values. Images of a 1000 mesh/inch gold grid were also obtained at the three focal planes. The grid scans indicated that the spatial resolution is about 2 (mu) in the image obtained at the third order focus.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A polarimeter for x-ray and vacuum ultraviolet (XUV) radiation was built to measure the spatial and spectral dependence of the polarization of the light produced by the new undulator at the U5 beamline at NSLS. The fourth-harmonic radiation was measured, and it does not agree with predictions based on ideal simulation codes in the far-field approximation.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The powerful beams of x-ray radiation generated by insertion devices at high power synchrotron facilities deposit substantial amounts of localized heat in the front end and optical components that they intercept. X-ray beams from undulator sources in particular are confined to very narrow solid angles and therefore impose very high absorbed heat fluxes. This paper is devoted to a detailed study of the design of windows for the Advanced Photon Source undulators and wigglers emphasizing alternative design concepts material considerations and cooling techniques necessary for handling the high heat load of the insertion devices. Various designs are thermally and structurally analyzed by numerically simulating full-power operating conditions. This analysis also has relevance to the design and development of other beam line components which are subjected to the high heat loads of insertion devices. Key indices: synchrotron radiation high heat load insertion devices undulators wigglers beryllium window. 2.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Insertion device (ID) synchrotron x-ray sources on present day and next-generation synchrotron facilities have very attractive spectral properties. In addition however they are capable of producing x-ray beams with large powers and in some cases unprecedented power densities. An overview of the spatial and frequency distributions of these sources including the effects of synchrotron particle beam emittance is presented. 1.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The Advanced Photon Source (APS) to be constructed at Argonne National Laboratory (ANL) utilizes magnetic devices which generate X-ray beams with very intense heat flux levels. The Fixed Mask Assembly (FMA) is the first component to interact with the X-ray beam. Two sets of a pair of FMA channels vertically and horizontally disposed contain the beam rather than define it. They are subject to very large heat fluxes during containment. In current practice the FMA channels are made of heavy seamless copper have rectangular cross-sections and are cooled internally with water. Channels are set at grazing angles ranging from 1 to 6 degrees with respect to the beam depending on the type of insertion device. APS insertion devices will impose higher heat fluxes on FMAs. Therefore a need exists to improve the FMA engineering keeping in mind the current design criteria and philosophy of FMAs. A comparative investigation of the conventionally achievable heat transfer coefficient h" with water and the wall conductance of a heavy wall copper tube reveals that major resistance is on the coolant side. Therefore there exists a significant opportunity to improve heat transfer in the tubes by enhancement of the coolant side. To this end an experimentally and analytically based research program has been adopted at the APS for investigating enhanced cooling methods and techniques. Currently a variety of copper wool filled tubes as well as a© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Spatial resolution and focusing efficiency are two important properties of a zone plate in x-ray focusing applications. A general expression of the zone plate equation describing its zone registration is derived from the interference of spherical waves emited from two mutually coherent point sources. An analytical expression of the focusing efficiency in terms of the zone plate thickness and x-ray refractive indices of the zones is also derived. Validity condition for using this expression is considered. Thickness required for obtaining adequate focusing efficiency is calculated as a function of x-ray energy for several representative materials. The spatial resolution of a finite thickness zone plate is worse than that of an infinetly thin zone plate which is approximately equal to the smallest zone width of the zone plate. The effect of the finite thickness on the spatial resolution is considered. This manuscript has been authored under contract number W-31-109-ENG-38 with the U. S. Department of Energy. Accordingly the U. S. Government retains a non-exclusive royalty-free license to publish or reproduce the published form of this contribution or allow others todo so for U. S. Government purposes. 146 / SPIE Vol 1345 Advanced X-Ray/EUV Radiation Sources andApplications(1990)© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.