Theoretical analysis of the role of Coulomb interactions in single and double photoionization of the helium dimer using numerical model simulations

Based on the results of numerical simulations we study scattering effects in single and double photoionization of the helium dimer. To this end we use a planar two-active-electron model of the helium dimer and abridged Hamiltonians in which different interactions between the electrons and the laser field and/or between the charged particles are removed from the full Hamiltonian. By comparing photoelectron angular distributions obtained in respective numerical simulations we are able to identify the role of the Coulomb interactions between the electrons and between the electrons and the nuclei for the primary as well as the knock-off electron in the processes.