Non-relativistic self-consistent-field calculation of two-photo transitions in atomic inner shells for Xe

Recent relativistic self-consistent-field calculations of two-photon decay rates involving atomic inner shells for Xe agreed very well with the recent experimental measurements of Xe(1s) -1 to (ns) -1 and (1s) -1 to (nd) -1 transitions (n=2, 3, 4), except for the (1s) -1 to (2s) -1 decay rate which had an unexplained discrepancy of a factor of 2.9 ((1s) -1 represents an 1s hole). Moreover the measurements deviated significantly from previous existing hydrogenic and non-relativistic self-consistent-field calculations. The authors present their non-relativistic self-consistent-field calculations which also are in fair agreement with the recent experimental measurements except for the (1s) -1 to (2s) -1 decay with a discrepancy by a factor of 3.3. The non-relativistic results provide a basis to study relativistic effects for the two-photon decay processes. Further relativistic theoretical and experimental studies would be necessary in order to elucidate the discrepancy in the (1s) -1 to (2s) -1 decay.