Polarization Transfer in the 2p_3/2 Photoionization of Magnesium-Like Ions

The inner-shell 2p_3/2 ionization of Mg-like Fe¹⁴⁺, Cd³⁶⁺, W⁶²⁺ and U⁸⁰⁺ ions by linear polarized light and the subsequent radiative decay are studied theoretically with the multiconfiguration Dirac–Fock (MCDF) method and the density matrix theory. Special attention is paid to exploring the influence of the polarization properties of the incident photon and the non-dipole term which arises from the multipole expansion of the electron-photon interaction on the properties of the subsequent x-ray radiation. The results show that there is a linear relationship between the degree of linear polarization of the radiative decay and ones of the incident light, which can be used for diagnosing the polarization of a light source. In addition, with the increasing photon energies, the non-dipole contribution to the alignment of the residual ions, the degree of linear polarization, as well as the angular distribution of the radiative decay following the inner-shell photoionization will also be increased.