Coster-Kronig transition

His theories include the Kronig-Penney model, the Coster-Kronig transition and the Kramers-Kronig relation.

If, in addition, the electron emitted (the "Auger electron") also belongs to the same shell, one calls this a super Coster-Kronig transition.

The Coster-Kronig transition is a special case of the Auger process in which the vacancy is filled by an electron from a higher subshell of the same shell.

The result are transitions of the type LMM and KLL along with faster Coster-Kronig transitions such as LLM.