Level-crossing determination of the 6s 6p P13 hfs of Hg193m

The magnetic-dipole and electric-quadrupole hfs interaction constants of 11-h Hg193m in the 6s 6p P13 state were determined from the observation of four level crossings. Previous studies relied on the observation of a single level crossing (W. W. Smith) and on optical spectroscopic data. The results, with second-order hyperfine, Zeeman, and cross Zeeman-hyperfine corrections are A=-2399.60(3) MHz and B=-655.6(18) MHz. The calculated hfs anomaly Δ199193m is 1.055(1)%, and the resulting electric-quandrupole moment is 1.2(1) b. The isotope shift is redetermined by the new hfs results.