Dielectronic recombination of U²⁸⁺ atomic ions

MITNIK, D. M.; PINDZOLA, M. S.; ROBICHEAUX, F.; BADNELL, N. R.; UWIRA, O.; MULLER, A.; FRANK, A.; LINKEMANN, J.; SPIES, W.; ANGERT, N.; MOKLER, P. H.; BECKER, R.; KLEINOD, M.; RICZ, S.; EMPACHER, L.

PHYSICAL REVIEW A - ATOMIC, MOLECULAR AND OPTICAL PHYSICS

AIP, The American Physical Society

Año: 1998 vol. 57 p. 4365 - 4372

1050-2947

Dielectronic recombination cross sections for U28+ are calculated in the distorted-wave approximation and compared with measurements obtained using an electron-ion merged beams apparatus. Although the experiment covered energies between 0 and 420 eV, the theoretical calculations were restricted to energies below 180 eV, where the most important resonance structures occur. The theoretical cross sections involving �n=0 excitations from the 5s25p2 ground configuration are found to be equally well described using either semirelativistic wave functions, as found in the AUTOSTRUCTURE codes, or fully relativistic wave functions, as found in the HULLAC codes. The main features of the experimental spectrum are well identified for the 80-180 eV energies, although complicated by the possible presence of unknown fractions of metastable levels. However, the resonance structures observed at the energies less than 80 eV, in the vicinity of a huge zero-energy peak, remain largely unexplained.