Determination of the ⁸⁷Rb 5p state dipole matrix element and radiative lifetime from the photoassociation spectroscopy of the Rb₂ 0_g^-(P_3/2) long-range state

We present a detailed study of the 0_g^-(P_3/2) pure long-range electronic state of the ⁸⁷Rb₂ molecule. The high-resolution spectral data provided by photoassociative spectroscopy of ⁸⁷Rb₂ is analyzed by using the generalized simulated annealing method. The dipole matrix element of the 5p ⁸⁷Rb atomic state and other effective asymptotic parameters for the 0_g^-(P_3/2) long-range state are determined and a complete analytical description of the potential well is obtained. We extract a radiative lifetime of the 5P_3/2 and 5P_1/2 states equal to 26.25(8) ns and 27.75(8) ns, respectively, with a precision (0.3%) comparable to atomic physics experiment.