Large-scale multiconfiguration Hartree-Fock and configuration-interaction calculations of the transition probability and hyperfine structures in the sodium resonance transition

Abstract

Results from large-scale multiconfiguration Hartree-Fock (MCHF) and configuration-interaction (CI) calculations of the transition probability and hyperfine structures in the sodium 3s${\mathrm{}}^{2}$S-3p${\mathrm{}}^{2}$P resonance transition are presented. In the calculations the orbital sets of the initial and final state wave functions were not restricted to be the same, but were optimized independently. The evaluation of the transition matrix elements was done using a technique where the two orbital sets are transformed so as to become biorthonormal, in which case standard Racah algebra can be used. Three-particle effects were taken into account in the CI calculations and were found to be important for the hyperfine structures, but less important for the transition probability. The calculated transition probability is in perfect agreement with the most recent experimental values, thus resolving the long-standing disagreement between theory and experiment. Also the 3s${\mathrm{}}^{2}$${\mathit{S}}_{1/2}$ and 3p${\mathrm{}}^{2}$${\mathit{P}}_{1/2,3/2}$ hyperfine interaction constants are in very good agreement with available experimental values. \textcopyright{} 1996 The American Physical Society.