Systematic study of visible transitions in Ti-like high Z ions

The magnetic dipole transitions between fine structure levels in the ground term of Ti-like ions, (3d(4)) D-5(2)-D-5(3), were investigated by observat ion of visible and near-UV light for several elements with atomic numbers f rom 51 to 78. The wavelengths are compared with theoretical values we recen tly calculated. The differences between the present calculations and measur ements are less than 0.6%. The anomalous wavelength stability predicted by Feldman, Indelicato and Sugar [J. Opt. Soc. Am. B 8, 3 (1991)] was observed . We attribute this anomalous wavelength stability to the transition from L S to JJ coupling and the asymptotic behavior of the transition energies in the intermediate coupling regime.