Double Auger decay in atoms: Probability and angular distribution

Abstract

Within many-body perturbation theory (MBPT), the correlated decay of an inner-shell vacancy, namely, the double Auger effect, is considered. Expressions for the amplitude and probabilities are obtained in the lowest order of MBPT. The approximate formulas, in particular the ``shakeoff'' model, are discussed. The calculations are performed for the 1${\mathit{s}}^{\mathrm{\ensuremath{-}}1}$\ensuremath{\rightarrow}2${\mathit{s}}^{\mathrm{\ensuremath{-}}2}$2${\mathit{p}}^{\mathrm{\ensuremath{-}}1}$+${\mathit{q}}_{1}$+${\mathit{q}}_{2}$ transition in Ne. It is shown that the angular distribution of electrons ejected in the double Auger decay of an s hole is asymmetric, depending strongly on the angle of their relative motion.