Triply differential cross section for double photoionization of helium. Comparison between theory and experiment.

We present a new method, based on the use of two-particle Green functions and projected electron-electron potential, for the calculation of triply differential cross sections (TDCS) for double photoionization of atoms and molecules. The main advantages of the method are the tunable accuracy of the results and its efficient applicability to molecules. We apply the method to the calculation of TDCS for double photoionization of helium at energies and geometries covered in recent experiments. Comparison with experiments and other calculations is very promising.