ISOTOPE SHIFTS AND HYPERFINE-STRUCTURE OF BA-134-138-II BY FAST-ION BEAM-LASER SPECTROSCOPY

We have measured the isotope shifts of the 5d-->6p transitions in Ba-1 34-138 II, of which the 5d(3/2)-->6p(1/2) transition has not been meas ured earlier. We have also obtained values with improved accuracy of t he magnetic dipole and electric quadrupole 6p(2)P degrees(1/2,3/2) lev els in Ba-135,Ba-137 II. The measurements are performed in the red and orange parts of the optical spectrum using fast ion beam-laser spectr oscopy with an improved procedure which avoids calibration of the ion velocity. A comparison with theory is made.