Inner-shell analytic relativistic radiative transition rates in screened potentials

Analytic expressions are obtained for relativistic radiative-decay rates of transitions between the $L$ and $K$ shells of intermediate- and high-$Z$ elements. These single-electron transition rates in a central potential can be expressed as a power series in the atomic scale parameter $\lambda$ which characterizes a small-distance expansion of the relativistic screened atomic potential. Retardation effects and all multipole contributions of the radiation field are included. With this approach it is possible to trace explicitly, both for the point Coulomb potential and for screening modifications, the role of relativistic, retardation, and higher multipole contributions in modifying the corresponding nonrelativistic dipole transition rates.