ENERGY-RESOLVED AND ANGLE-RESOLVED DOUBLE PHOTOIONIZATION IN ARGON LEADING TO THE 3P(-2)(1)D(E) FINAL IONIC STATE

Triple differential cross sections (TDCS) of argon double photoionization to the Ar2+ (3p-2 1De) final ionic state have been measured at selected photon energies by means of energy- and angle-resolved electron-electron coincidences. The situation of resonance affected double ionization, i.e. direct double photoionization interfering with the population of satellite states which autoionize to the same final state, manifests itself strongly in the shape of the experimental TDCS patterns. At photon energies where the influence of the indirect channel is weak, the experimental data are qualitatively compared with theoretical predictions based on the individual contributing electron-pair wavefunctions as given by the extended Wannier theory.