Hard x-ray absorption spectroscopy for pulsed sources

Abstract

We present a method suitable for the measurement of a high-energy resolved absorption spectrum in the emission mode upon target excitation with an intense monochromatic pulse of x-ray light. The approach is based on a measurement of a single resonant Raman x-ray spectrum at a fixed off-resonant excitation energy by a dispersive-type high-resolution emission spectrometer. Using a simple Lorentzian tail correction function and an energy-scale transformation, we reconstructed the ${L}_{3}$ absorption edge of Xe from the $3d$-$2{p}_{3/2}$ resonant Raman x-ray spectrum recorded at excitation energy 25 eV below the ${L}_{3}$ edge. The energy resolution is well below the ${L}_{3}$ core-hole lifetime broadening and allows for a straightforward extraction of the $[2{p}_{3/2}]n\ensuremath{\ell}$ resonance energies and emission strengths. The reconstructed spectrum is nearly equivalent to the high-energy resolution fluorescence detected absorption spectrum, which is recorded by scanning the photon excitation energy across the absorption edge.