A double-photoionization study of calcium atoms for equal and unequal electron energy sharing

The triple differential cross section (TDCS) for double photoionization of calcium atoms has been studied, in the region of the Ca 3p --> 3d giant res onance, for equal and unequal energy sharing by the two electrons. The meas urements were performed at two different photon energies corresponding to d ifferent resonance symmetries, and the results show that the TDCS is strong ly resonance dependent. For a fixed total energy the TDCS, at a relative an gle of 180 degrees for the two electrons, has been found to increase approx imately linearly with increasing energy of one of the electrons.