A many-body calculation of the hyperfine interaction in the lowest2 S and2 P states of li-like systems

Abstract

Abstract. A non-relativistic perturbation method of Brueckner-Goldstone type is used to calculate the hyperfine interactions in the lowest 2S and 2p states of the Li-like systems, Li, Be +, B z+, C a+, N 4+, 0 5+ and F 6+. The effect of the polarization of the closed shell is treated to all orders of perturbation, while the correlation effect is calculated in the lowest order, i.e. in the third order of the perturbation expansion. Experimental data are at present available only for Li, Be § and E 6+, and the agreement with the calculated values is in these cases very good, usually within the experimental uncertainties. This implies that the predictions made in the remaining cases should be quite reliable, which may simplify the experimental determination of these quantities. Theoretical values are also given for the quadrupole interaction, which can be used to determine the nuclear quadrupole moments, when accurate experimental information becomes available.

Fine and hyperfine structure of the two lowest bound states of Be? and their first two ionization thresholds

“…For Be+ 2S, our results for the single HFS constant are compared with experiment [24] and other correlated results [32]. The result is that the discrepancy between theory and experiment has been greatly reduced.…”

Analysis of the hyperfine structure of the 4s 4p configuration in Ca and the nuclear quadrupole moment of43Ca

“…In addition to all the second-order diagrams in Fig. 3 all higher-order core-polarization diagrams have been evaluated using an iterative procedure [22]. Examples of two fourth-order core-polarization diagrams of the kind included here are shown in Fig.…”

Ab-initio calculations of pair-correlation effects on the hyperfine structure of the 4s 4p and 4s 3d configurations of Ca

“…The correlation between the core and the valence electrons was found to affect the valence electrons considerably. The effects on the hyperfine structure from single excitations induced in the core by the valence pair (core polarisation effects) is calculated using hyperfine-induced single-particle functions [14] which do not depend on the state of the valence electrons. The remaining correlation effects involving only one valence electron at a time, taken from [6], are also added.…”