K-shell electron-impact excitation and polarization of x-ray emission of Fe²⁰⁺ ion

The total and magnetic cross sections for K-shell electron impact excitation (EIE) of Fe²⁰⁺ have been calculated using the fully relativistic distorted-wave approach. Degrees of linear polarization of x-ray emission following EIE are presented for several stronger 2p→1s transitions, and compared with the values for the same transition lines but from dielectronic recombination process of Fe²¹⁺ in the ground state, obvious differences are found that can be employed in diagnosing the formation mechanism of corresponding x-ray lines.