Figure 2.

Transient SXR absorption spectra at the carbon K-edge. (a) Measured absorption spectra of neutral ethanol and methanol before (thin solid lines) and after (dashed lines) strong-field ionization. The pumped spectra were averaged over delays ranging from t = 50–250 fs. The difference spectra ΔOD are shown as thick solid lines. These data have been recorded with the CCD camera. (b) Calculated X-ray absorption spectrum of the methanol dimer cation (red area) and neutral methanol dimer in its ground state (blue area) spectra. The spectra of the cation have been obtained by integration over the simulated time interval. The difference between the two spectra, corresponding to the ΔOD, is shown as a solid purple line. (c) Schematic representation of the molecular orbitals of the ethanol molecule and the observed X-ray transitions.