Configuration-interaction-induced dynamic spin polarization of the Ar*(2p1/2,3/2-14s1/2)J = 1 resonant Auger decay

Spin-resolved measurements of the Ar*(2p1/2,3/2-14s1/2)J = 1 resonantly excited L2,3M2,3M2,3 Auger decay have been performed. The low resolution Auger spectrum, which due to cancellation between different multiplet components should exhibit virtually zero dynamic spin polarization, reveals an unexpected nonvanishing polarization effect. Calculations within a relativistic distorted wave approximation explain this effect as configuration-interaction (CI) induced. The CI generates experimentally unresolved fine structure components with low and high total angular momentum, giving rise to asymmetric cases where the high J part of certain multiplets is suppressed by internal selection rules for diagram lines. In this case, only the low J components survive with no partner for spin-polarization cancellation.