Single-shot hyperspectral imaging and beam characterization using soft x-ray free-electron laser

The intense brightness of x-ray free electron lasers enables the capture of instantaneous sample states. A Wolter mirror imaging system has been developed in the soft x-ray region to acquire magnified images of samples with a single shot, before radiation damage occurs. We have developed a single-shot spectro-microscopy that combines integrated diffraction gratings with twin Wolter mirrors. This system functions as a two-dimensional dispersive spectrometer, obtaining absorption spectra at each point of the magnified image. Proof-of-principle experiments were performed at the soft x-ray beamline BL1 of SACLA. The system was designed with spatial and energy resolutions of 1.67μm and 1000 in E/ΔE, respectively. The spatial distribution of the absorption spectra provided information on the chemical components of the sample. Additionally, the spectra of the illumination beam at the objective plane were found to vary both shot-by-shot and spatially.