Photoionization of atoms in excited states

This paper gives a review of photoionization studies in atoms in which an outer electron has been promoted onto an excited orbital. The various experimental methods presently available for such studies are briefly described. Examples are given to illustrate the type of information which can be extracted from the few experiments carried out so far. Special emphasis is put on the first successful experiment combining the use of a cw dye laser tuned to the first resonance line and of synchrotron radiation to observe electrons produced by inner shell and outer shell photoionization of excited Na and Ba atoms. 53 references, 13 figures