Single-shot X-ray absorption spectroscopy at X-ray free electron lasers

Overview & Synopsis

X-ray Absorption Spectroscopy (XAS) is a widely used diagnostic method for studying electronic and structural properties of matter. At first glance, the relatively narrow bandwidth highly fluctuating spectral structure Free Electron Lasers (XFEL) sources seem to require accumulation over many shots achieve high data quality. To date best approach implementing XAS at XFEL facilities has been using monochromators scan photon energy across desired range. While this possible easily reproducible samples such as liquids, it incompatible with important systems. Here, we demonstrate collection single-shot spectra 10s eV an source, error bars only few percent. We additionally show how extend technique wider ranges towards Extended Fine Structure measurements, by concatenating tens measurements. Our results pave way future studies XFELs, in particular those femtosecond regime. This advance envisioned be especially transient processes that can initiated lower repetition rates, difficult reproduce excitation conditions, or rare samples, encountered high-energy density physics.