Radiative recombination of an electron with multiply charged uranium ions

Precise relativistic calculations of the total and differential cross sections of radiative recombination of an electron with hydrogen-, helium-, and lithium-like uranium ions with energies in the range of 1–1000 MeV/amu1 for the cases of capture of an electron to the K and L shells are performed in terms of the Dirac-Fock method. The influence of electron-electron interactions, including the magnetic Breit interaction, on this process is studied, as well as the effect of the basic quantum electrodynamic corrections. The discrepancy between the results obtained and data on the total and differential cross sections calculated for the case of recombination of an electron in the Coulomb field of a bare nucleus, which were reported in most previous publications and used to interpret the results of experiments, is considered. It is found that, for the uranium ions under consideration, the contribution of electron-electron interaction and other corrections may be as high as 11%. This contribution is larger for similar ions of lighter elements; it also increases with decreasing degree of ionization of the uranium ions. The calculated angular distribution of unpolarized photons emitted in the case of capture of electrons to the K and L shells of the U91+, U90+, and U89+ ions is in good agreement with the experimental data.