Two-photon double ionization of the hydrogen molecule

Cross sections for the removal of both electrons of the hydrogen molecule by two photons are presented at 30 eV photon energy using the time-dependent close-coupling method. Our approach allows detailed information about the dynamics of the ionization process to be extracted, including angular distributions for the outgoing electrons. Analysis of our calculations reveals some similarities to the analogous process of two-photon double ionization of helium, but also uncovers some purely molecular effects. For example, we find that the differential cross sections vary with the kinetic energy released to the outgoing protons if the molecule is parallel to the polarization direction, but do not vary if the molecule is perpendicular to the polarization direction.