Radiative and Auger transitions of core-excited states for the boron isoelectronic sequence

Abstract

Energy levels, radiative rates, Auger branching ratios of the 1s vacancy resonances 1s2s 22p 2 and 1s2s2p 3 2,4L (L = S, P, D) of the boron isoelectronic sequence including O3+, Ne5+, Mg7+, Si9+ ions are calculated by the saddle-point variation and saddle-point complex-rotation methods. Large-scale wavefunctions are used to obtain reliable results. Relativistic corrections and mass polarisation effects are taken into account to get precise energy levels. Calculated X-ray wavelengths, radiative rates, Auger electron energies, and Auger rates for these core-excited states are compared with available theoretical and experimental results. Furthermore, calculated reliable X-ray wavelengths are used to give possible identifications for satellite lines in the X-ray spectrum of foil-excited magnesium and silicon ions. Calculated Auger electron energies and Auger branching ratios are used to identify oxygen and neon Auger electron spectral lines in previous collision experiments. Three unidentified experimental spectral lines in neon KLL Auger electron spectrum are identified in the present work. The total radiative rates and the total Auger rates for the 1s2s 22p 2 and 1s2s2p 3 resonances of B-like ions are also discussed, as a function of atomic number Z. It is found that the total Auger rates of these resonances are several orders of magnitude larger than the total radiative rates for these low-Z (Z = 6–14) ions.