Dominance of double processes in complete Auger decay of Rb+(3d−1)

Abstract

The complete Auger decay of ${\mathrm{Rb}}^{+}(3{d}^{\ensuremath{-}1})$ including single and double processes is investigated using the distorted wave approximation. The direct double Auger decay was calculated by separating the knock-out and shake-off mechanisms. For single Auger decay of the $3{d}^{\ensuremath{-}1}$ hole state, it is generally believed that the dominant channels should be levels belonging to the configurations of $[1{s}^{2}2{s}^{2}2{p}^{6}3{s}^{2}3{p}^{6}3{d}^{10}]4{s}^{2}4{p}^{4}5s$, $4s4{p}^{5}5s$, and $4{s}^{0}4{p}^{6}5s$. Here we predict that the strongest channels originate from $4{s}^{2}4{p}^{3}4d5s$, which accounts for 36.3% of the single Auger decay rate. The levels belonging to this configuration can further decay to ${\mathrm{Rb}}^{3+}$, resulting in a large fraction of cascade double Auger decay. Moreover, the probability of direct double Auger decay in Rb is also high because of its $5s$ electron. The branching ratios of cascade and direct double Auger decay are predicted to be 50.60% and 22.13%, respectively, resulting in the dominance of double Auger decay with a fraction of 72.73% in the complete Auger decay of ${\mathrm{Rb}}^{+}(3{d}^{\ensuremath{-}1})$.