Double Photoionization of Mg and the Scaling Model

Direct double photoionization of atoms in which two electrons are simultaneously emitted is of high interest for understanding electron correlations. Of particular interest are the alkaline-earth metals that are heliumlike atoms insofar as they only have two outer-valence electrons while the other electrons can be approximated as spectators [1]. The experiments were performed on the Wadsworth beamline, the U1-NIM beamline, and on the PGM beamline [2,3]. The Mg photoions created in our vacuum chamber are analyzed and detected by an ion time-of-flight spectrometer using a pulsed electric field across the interaction region.