Calculation of the photoionization with de-excitation cross sections of He and helium-like ions

Abstract

We discuss the results of the calculation of the photoionization with de-excitation of excited He and helium-like ions Li${}^{+}$ and B${}^{3+}$ at high but non-relativistic photon energies $\omega$. Several lower ${}^{1}S$ and ${}^{3}S$ states are considered. We present and analyze the ratios $R_d^{+\ast }$ of the cross sections of photoionization with de-excitation, ${\sigma }_{(d)}^{+\ast }(\omega )$, and of the photo-ionization with excitation, ${\sigma }^{+\ast }(\omega )$. The dependence of $R_d^{+\ast }$ on the excitation of the target object and the charge of its nucleus is presented. Apart to theoretical interest, results obtained can be verified using such long living excited state as $2^{3}S$ of He.

10 pages, 6 tables