Isolated Core Excitations in Static Fields

A basic theory will be presented for the photo-excitation of a core state of a Rydberg atom in any type of static field; in this situation, the core state is excited by the photon while the Rydberg electron is essentially a spectator. This simple picture is made interesting through the interaction of the Rydberg electron with the core. This interaction can cause the Rydberg electron's state to change during the photo-absorption and can cause autoionization. The results of ab initio calculations will be compared to experimental photo-ionization cross sections for Mg and Ba in static electric fields. Some general properties of this process will be discussed.