Bagschik, K.; Schneider, M.; Wagner, J.; Buss, R.; Riepp, M.; Philippi-Kobs, A.; Muller, L.; Roseker, W.; Trinter, F.; Hoesch, M.; Viefhaus, J.; Eisebitt, S.; Grubel, G.; Oepen, H.P.; Fromter, R.: Enabling time-resolved 2D spatial-coherence measurements using the Fourier-analysis method with an integrated curved-grating beam monitor. Optics Letters 45 (2020), p. 5591-5594
10.1364/ol.402264
Open Accesn Version
Abstract:
Direct 2D spatial-coherence measurements are increasingly gaining importance at synchrotron beamlines, especially due to present and future upgrades of synchrotron facilities to diffraction-limited storage rings. We present a method to determine the 2D spatial coherence of synchrotron radiation in a direct and particularly simple way by using the Fourier-analysis method in conjunction with curved gratings. Direct photon-beam monitoring provided by a curved grating circumvents the otherwise necessary separate determination of the illuminating intensity distribution required for the Fourier-analysis method. Hence, combining these two methods allows for time-resolved spatial-coherence measurements. As a consequence, spatial-coherence degradation effects caused by beamline optics vibrations, which is one of the key issues of state-of-the-art X-ray imaging and scattering beamlines, can be identified and analyzed.