Many-body effects in the photoionization of radon

The total and partial photoionization cross sections, branching ratios, and photoelectron angular-distribution asymmetry parameters have been calculated for atomic radon (Z=86) for all subshells from the 6p valence shell down to the deep n=3 subshells. The relativistic random-phase approximation, the relativistic random-phase approximation modified to include relaxation effects, and the relativistic random-phase approximation modified to include relaxation effects and Auger decay were all used to determine the relative importance of various many-body effects such as interchannel coupling, core relaxation, and Auger decay. Comparisons are made between the various theoretical models and experimental data for the total cross sections. Interchannel coupling among many channels was found to be important in calculations of the total cross sections for most shells, and relaxation effects were found to be substantial for the n=5 shell.