Hyperfine splitting and isotope shift in the optical transition \(\)of \(\)Eu isotopes and electromagnetic moments of \(\)Eu

The laser-induced resonance fluorescence in an atomic beam was used in order to measure the hyperfine splitting of the 4f7 6s2\(\) and 4f7 6s6p\(\) levels in 151,153,155Eu isotopes. The hfs constants A and B of the unstable 155Eu were determined for the first time: \(\) MHz, \(\) MHz and \(\) MHz. With these data and after corrections for second-order hyperfine structure perturbations the nuclear moments of 155Eu were deduced: \(\) n.m. and \(\) b. In addition new and more precise values of the hfs constants of the excited state for the stable 151,153Eu were obtained. They are as follows: \(\) MHz, \(\) MHz and \(\) MHz, \(\) MHz. The hyperfine anomalies \(\)% and \(\)% were extracted from the corrected hfs constants.