15min:

FANG WANG AND TIMOTHY C. STEIMLE, Department of Chemistry and Biochemistry, Arizona State University, Tempe,AZ 85287; MICHAEL HEAVEN, Department of Chemistry, Emory University, Atlanta,GA 30322.

Thorium monoxide, ThO, has recently attracted interest as a possible venue for the determination of the electric dipole moment of the electron, d_e. Here we report on the results of an optical Stark study of the E(O⁺)-X^{1 +}(1,0) band and the field-free study of the F(O⁺)-X^{1 +}(0,0) band. A supersonic molecular beam of ThO was generated using a laser ablation technique and probed using laser excitation spectroscopy. The determined values for the permanent electric dipole moments, µ_el, for the E(O⁺)(v=1) and X^{1 +}(v=0) vibronic states were determined to be 3.534\pm0.010 D and 2.782\pm0.012 D, respectively . The dispersed laser induced fluorescence resulting from the excitation of the E(O⁺)-X^{1 +}(1,0) and F(O⁺)-X^{1 +}(0,0) bands have been recorded and the results are compared to Franck-Condon predictions. The radiative lifetimes for the E(O⁺)-X^{1 +}(1,0) band F(O⁺)-X^{1 +}(0,0) bands were determined.