An experimental and theoretical study of the 3p photoionization of Ca based on a measurement of the angular correlation between the photoelectrons and Auger electrons

We have studied the photoionization of the 3p electron of Ca in the vicinit y of its ionization threshold by means of both an angular correlation measu rement between the 3p photoelectron and the M3N1N1 Auger electron, and conv entional angular distribution measurements for both the 3p photoelectron an d the M3N1N1 Auger electron. We have carried out 'random phase approximatio n with exchange' calculations for the Ca 3p photoionization process, and th e results are in good agreement with the amplitudes and phase differences e xtracted from the experimental data.