Hyperfine structure studies of the odd-parity electronic levels of the holmium atom. I: Levels with known energies

Abstract

In this work investigations of the hyperfine structure of 66 spectral lines of the holmium atom were performed with the method of laser induced fluorescence in a hollow cathode discharge lamp. Altogether 43 odd-parity levels, involved as the upper levels in the transitions studied, were investigated. For about half of them the hfs constants A and B were evaluated for the first time. For some levels, already examined in earlier works, supplementary results were obtained; for a few levels it was possible to compare our results with earlier literature data. For 4 levels J quantum numbers were changed with respect to the available literature values. As a by-product, also improved hfs constants for the lower even-parity levels were determined. The data reported facilitated the semi-empirical fit of the fine and hyperfine structure of the odd-parity level system, performed in our group.