Emission intensities are reported for multiplet components of three metastable autoionizing OI3P0levels with nanosecond lifetimesmdash;the 2s2p53P0, 3sPrime;3P0, and 3dprime;3P0states. Emission intensities for the 3sPrime;3P0and 3dprime;3P0states are nonstatistical, i.e., the observed intensities for components of the multiplets do not correspond to the theoretical statistical absorption intensities. Autoionization, prohibited for these states in a pure Russellminus;Saunders coupling scheme, proceeds via weaker spinminus;orbit or spinminus;spin interactions, primarily through direct interaction with available continua. Previous autoionization studies of all of these states showed that the autoionization intensities are nonstatistical only for the 2s2p53P0and 3sPrime;3P0states. These results are explained in terms of a competition between autoionization and emission based on a comparison of the true lifetimes of the states and the radiative lifetimes calculated from the absorption oscillator strengths. When the autoionization and emission lifetimes are comparable, both decay channels show nonstatistical behavior; when one decay channel dominates, only the minor decay channel shows nonstatistical behavior. The nonstatistical nature of the decay is discussed in terms of selective autoionization of certain total angular momentum levels of the decaying3P0states; however, additional theoretical work is required to establish the origin of this effect.
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