Mg 3pnd (J=3) autoionization spectra using isolated-core excitation.

Abstract

The Mg 3pnd J=3 autoionizing spectra have been studied for n values ranging from 9 to 40, using an isolated-core excitation technique with ion detection. The measured spectra are found to be in generally excellent agreement with results from a calculated reaction matrix. The observed spectra exhibit strong interseries interactions between the 3${\mathit{p}}_{1/2}$${\mathit{nd}}_{5/2}$ and 3${\mathit{p}}_{3/2}$${\mathit{nd}}_{\mathit{j}}$ series, and, for n\ensuremath{\le}15, interferences between the amplitudes for excitation of the core electron to the 3${\mathit{P}}_{1/2}$ and 3${\mathit{P}}_{3/2}$ ion states. Classifications of states for n\ensuremath{\le}29 are tabulated. We discuss the difficulties in deducing autoionization rates for Mg from the experimental and theoretical data, the implications of which could have relevance to dielectronic recombination rate calculations.