Fluorescence branching ratios and magnetic tuning of the visible spectrum of SrOH

Abstract: The magnetic tuning of the low rotational levels in the Xsigma+(0,0,0), Api(0,0,0), and Bsigma+ (0,0,0) electronic states of strontium hydroxide, SrOH, have been experimentally investigated using high resolution optical Zeeman spectroscopy of a cold molecular beam sample. The observed Zeeman shifts and splittings are successfully modeled using a traditional effective Hamiltonian approach to account for the interaction between the Api and Bsigma+ states. The determined magnetic g-factors for the Xsigma+, Api , and Bsigma+ states are compared to those predicted by perturbation theory. The dispersed fluorescence resulting from laser excitation of rotationally resolved branch features of the Bsigma+ (0,0,0)<Xsigma+(0,0,0) Api(0,0,0)< Xsigma+(0,0,0) transitions have been recorded and analyzed. The measured fluorescence branching ratios are compared with Franck-Condon calculations. The required bending motion wave functions are derived using a discrete variable representation (DVR) method. Implications for laser slowing and magneto-optical trapping experiments for SrOH are described.