New hyperfine structure data of atomic terbium measured by laser spectroscopic methods

A hollow cathode discharge lamp, a tunable Ti-Sa laser and laser-induced fluorescence spectroscopy were used to examine the hyperfine structure of atomic terbium. A total of 39 spectral lines in the wavelength range between 695 nm and 780 nm were examined. For 11 levels of even parity and 26 levels of odd parity, the magnetic dipole hyperfine structure constants A, and the electric quadrupole hyperfine structure constants B, were determined. For 13 of these levels, the hyperfine structure constants had not been previously published. Furthermore, for two levels, the hfs constants A and B from the literature were found to be completely different from our values. Given that our spectra had better resolution and sensitivity compared to the relevant literature source, and that our values were determined using two different lines, we consider our values to be the more reliable ones.