Use case 13 – Effects on the spot quality of the mirror error profile and source pointing instability
While assessing the performance of X-Ray optics, the focusing sharpness of the mirror is evaluated under different conditions. An important parameter is the beam pointing stability. When combined with the local curvature changes due to the mirror surface defects, pointing instability can induce shifts of the focal plane, or equivalently a broadening of the spot size at the sample stage.
By means of WISER, it is possible to assess the variation of the focal plane and of the spot size as function of the incidence angle on the mirror (which is varied around the nominal incidence value).
Use Case action flow
- Compose a beamline in WISER
- Decide max and minimum deviation angles.
- Perform a preliminary simulation to assess the longitudinal range where to search for the best focus. Such preliminary simulation shall be done between max and min deviation angles.
- For each sampled angle within the selected range at 2, compute the HEW at the best focus (this operation might be time consuming: approximately half an hour).
- Plot the focus position and the spot size.
Since 2015 WISER is an original product of the PADReS Photon Transport group (FERMI) and the Optics Group (ELETTRA), developed by M.Manfredda and L. Raimondi. With the support of A. Hafner (CERIC-ERIC) and of PANOSC, it has been provided a more powerful Graphic Interface in OASYS, for a better user (and scientist) experience.
Publisher’s link: https://onlinelibrary.wiley.com/iucr/doi/10.1107/S1600577519010099