Franck-Condon Factors and Radiative Lifetime of the A^{2}\Pi_{1/2} - X^{2}\Sigma^{+} Transition of Ytterbium Monoflouride, YbF

The fluorescence spectrum resulting from laser excitation of the A^{2}\Pi_{1/2} - X^{2}\Sigma^{+} (0,0) band of ytterbium monofluoride, YbF, has been recorded and analyzed to determine the Franck-Condon factors. The measured values are compared with those predicted from Rydberg-Klein-Rees (RKR) potential energy curves. From the fluorescence decay curve the radiative lifetime of the A^{2}\Pi_{1/2} state is measured to be 28\pm2 ns, and the corresponding transition dipole moment is 4.39\pm0.16 D. The implications for laser cooling YbF are discussed.Comment: 5 pages, 5 figure

The pure rotational spectrum of YbOH

The pure rotational spectrum of YbOH has been recorded and analyzed to produce fine and magnetic hyperfine parameters for the X^2Σ^+(0,0,0) state. These parameters are compared with those determined from the optical study [Melville and Coxon, J. Chem. Phys.115, 6974-6978 (2001)] and with the values for YbF [Dickinson et al.115, 6979-6989 (2001)]. The results support the existence of an unobserved perturbing state near the A^2Π_(1/2) state, similar to that previously found in YbF. The precisely determining parameters lays the foundation for laser cooling YbOH, which will aid in the search for new physics beyond the standard model

Branching Ratios, Radiative Lifetimes and Transition Dipole Moments for YbOH

Medium resolution (Δν~ 3 GHz) laser-induced fluorescence (LIF) excitation spectra of a rotationally cold sample of YbOH in the 17300-17950 cm⁻¹ range have been recorded using two-dimensional (excitation and dispersed fluorescence) spectroscopy. High resolution (Δλ~ 0.65 nm) dispersed laser induced fluorescence (DLIF) spectra and radiative decay curves of numerous bands detected in the medium resolution LIF excitation spectra were recorded. The vibronic energy levels of the X²Σ state were predicted using a discrete variable representation approach and compared with observations. The radiative decay curves were analyzed to produce fluorescence lifetimes. DLIF spectra resulting from high resolution (Δν < 10 MHz) LIF excitation of individual low-rotational lines in the A²Π_(1/2)(000)-X²Σ((000), A²Π_(1/2)(100)-X²Σ((000), and [17.73]Ω=0.5-X²Σ((000) bands were also recorded. The DLIF spectra were analyzed to determine branching ratios which were combined with radiative lifetimes to obtain transition dipole moments. The implications for laser cooling and trapping of YbOH are discussed