Near K-edge Photoionization and Photoabsorption of Singly, Doubly, and Triply Charged Silicon Ions

Abstract Experimental and theoretical results are presented for double, triple, quadruple photoionization of Si + 2+ ions double 3+ by a single photon. The experiments employed the photon–ion merged-beams technique at synchrotron light source. experimental photon-energy range 1835–1900 eV comprises resonances associated with excitation 1 s electron to higher subshells subsequent autoionization. Energies, widths, strengths these extracted from high-resolution measurements, core-hole lifetime K-shell ionized neutral silicon is inferred. In addition, cross sections photoabsorption multiple were obtained large-scale multiconfiguration Dirac–Hartree–Fock calculations. present calculations agree experiment much better than previously published results. importance an accurate energy calibration laboratory data pointed out. benchmark particularly useful discriminating between absorption in gaseous solid component (dust grains) interstellar medium.