The Xe 4${\mathit{d}}_{5/2}$:4${\mathit{d}}_{3/2}$ branching ratio has been determined in the photon energy range 80–250 eV using high-resolution electron spectroscopy and undulator radiation at the new Finnish beamline at the MAX I storage ring. The results were found to be in a satisfactory agreement with the calculated literature values obtained with the relativistic random-phase approximation. A few discrepancies between the theoretical predictions and our experimental results indicate additional correlation effects not accounted for in theory. The branching ratio is now shown to have a maximum of about 1.6 at around 230 eV. Lifetime widths of 114(4) and 121(4) meV are obtained for the 4${\mathit{d}}_{3/2}$ and 4${\mathit{d}}_{5/2}$ core hole states, respectively.

• Received 20 June 1994

DOI:https://doi.org/10.1103/PhysRevA.51.855