Nonstatistical behavior of the photoionization of spin-orbit doublets

The photoionization branching ratios of spin-orbit doublets are studied both experimentally and theoretically at energies several keV above threshold. The results show significant relativistic effects for Ar 2p in the autoionizing region below the 1s threshold, and large many-body effects for Xe 3d and 4d in the vicinity of the L-shell thresholds. The branching ratios in Xe are also found to vary significantly over very broad multi-keV energy regions both above and below the inner-shell thresholds. In addition, the Ar 2p study confirms experimentally the decades-old theoretical prediction that the nonresonant branching ratio does not approach the statistical (nonrelativistic) value, and, in fact, progressively diverges from statistical with increasing photon energy.

Automated summary

The research examines the photoionization branching ratios of spin-orbit doublets at energies several keV above threshold, showing relativistic effects in Ar and many-body effects in Xe. Significant variations in branching ratios over broad energy regions are found in Xe. Additionally, the experimental confirmation of the theoretical prediction regarding nonresonant branching ratios diverging from the statistical value with increasing photon energy is observed in the study of Ar 2p.