Precision Measurements of the 138Ba+ 6s2S1/2 -5d2D5/2 Clock Transition

Measurement of the Ba-138(+) S-2(1/2) - D-2(5/2) clock transition frequency and D-5/2 Lande g(J) factor are reported. The clock transition frequency v(Ba+) = 170126432449333.31 +/- (0.39)(star) +/- (0.29)(sys) Hz, is obtained with accuracy limited by the frequency calibration of the maser used as a reference oscillator. The Lande g(J) factor for the D-2(5/2) level is determined to be g(D) = 1.20036739(24), which is a 30-fold improvement on previous measurements. The g-factor measurements are corrected for an ac-magnetic field from trap-drive-induced currents in the electrodes, and data taken over a range of magnetic fields underscores the importance of accounting for this systematic.