Photoelectron–photoion coincidence momentum imaging for dissociative ionization of ethanol in intense laser fields

Ionization dynamics of ethanol in intense laser fields is investigated by photoelectron–photoion coincidence momentum imaging. Comparisons are made among the photoelectron images for the four different single ionization channels; the parent ion formation, H elimination, CH3 elimination, and OH elimination. At the intensity of 9.3 TW/cm2 with the duration of 35 fs, the electronically excited states are prepared directly in the ionization for the CH3 and OH elimination. As the pulse becomes longer and stronger, the ionization to the electronic ground state becomes dominant even for the CH3 and OH elimination, suggesting the efficient electronic excitation subsequent to the ionization.