Figure 4.

Experimental setup, showing both the light sources and the SXR beamline. The pump and probe pulses are overlapped on the liquid flat jet. The small crossing angle of 0.5° ensures negligible temporal smearing of <3 fs. The inset illustrates the geometry of the flat-jet sample and the liquid-nitrogen cold trap that captures the majority of the liquid. The SXR probe is generated in a differentially pumped high-harmonic gas cell and refocused using a toroidal mirror. Finally, the spectrometer consists of a flat-field grating and an X-ray CCD camera.