ANL, Lemont, Illinois, USA
An electronic autocollimator is a valuable tool that can assist in the alignment of optical beamline components such as mirrors and monochromators. It is also a powerful tool for in situ diagnoses of the mechanical behavior of such components. This can include the repeatability of crystals, gratings, and mirrors as they are rotated; the parasitic errors of these same optical elements as they are rotated and/or translated; and the repeatability and parasitic errors as bendable mirrors are actuated. The autocollimator can even be used to establish a secondary reference if such components require servicing. This paper will provide examples of such alignments, diagnoses, and references that have been made with an autocollimator on existing and recently commissioned beam-lines at the Advanced Photon Source (APS). In addition, this paper will discuss how this experience influenced the specifications and subsequent designs of the new primary high-heat-load mirror systems (PHHLMS) that are currently under fabrication for six of the APS Up-grade (APS-U) feature beamlines. Each mirror was specified to provide in situ line-of-sight access for an autocollimator to either the center of the mirror’s optical surface or to a smaller polished surface centered on the backside of each mirror substrate. This line of sight will be used for initial alignment of the mirror and will be available for in situ diagnoses if required in the future.
WEPC06
ANL, Lemont, Illinois, USA
Thermal deformation of x-ray optics can have a profound impact on beamline performance. The thermal deformation of these x-ray optics due to heat loads of the x-ray beam has been previously shown to be able to be partially mitigated by adding a groove or notch on the side of the optic and below the optical surface. This notch acts as a thermal break which allows for anti-clastic bending and the notch geometry can be optimized for various heat loads. By optimizing the notch height, depth, and distance from the optical surface the thermal deformation on the optic can be minimized. The High Heat Load Mirror systems of the Advance Photon Source (APS) feature beamlines rely on this notch geometry to be able to take full advantage of the new source of the APS Upgrade.