Tracing direct and sequential two-photon double ionization ofD2in femtosecond extreme-ultraviolet laser pulses

Y. H. Jiang, A. Rudenko, E. Plésiat, L. Foucar, M. Kurka, K. U. Kühnel, Th. Ergler, J. F. Pérez-Torres, F. Martín, O. Herrwerth, M. Lezius, M. F. Kling (+14 others)
2010 Physical Review A. Atomic, Molecular, and Optical Physics  
Two-photon double ionization (TPDI) of D 2 is studied for 38-eV photons at the Free Electron Laser in Hamburg (FLASH). Based on model calculations, instantaneous and sequential absorption pathways are identified as separated peaks in the measured D + + D + fragment kinetic energy release (KER) spectra. The instantaneous process appears at high KER, corresponding to ionization at the molecule's equilibrium distance, in contrast to sequential ionization mainly leading to low-KER contributions.
more » ... R contributions. Measured fragment angular distributions are in good agreement with theory.
doi:10.1103/physreva.81.021401 fatcat:y2cnwhnr4bhfjjwtwv2u2wo32m