Femtosecond X-ray fluorescence from light elements excited by laser harmonics

Summary form only given. We report the observation of K-shell vacancies in light elements, such as boron and carbon, by means of X-ray fluorescence using sub-10-fs-pulse-driven coherent laser harmonics as the excitation source. The experiments represent the first application of coherent water-window radiation produced by a laboratory source and are a first step towards time-resolved X-ray spectroscopy of solid-state and molecular dynamics on a sub-100-fs time scale.