Measurement of the Rb(5D5/2) photoionization cross section using trapped atoms -: art. no. 043411

We report on measurements of the cross section for photoionization of Rb atoms in the highly excited 5D(5/2) level at wavelengths ranging from 1064 to 532 nm (photoelectron energies of 0.175 to 1.33 eV). We efficiently populate the 5D(5/2) level using coherent two-photon excitation of trapped atoms with pulses in the counterintuitive order. The absolute photoionization cross sections are then measured via the increased loss of atoms from the magneto-optical trap when it is illuminated by the photoionizing light. Out results are in good agreement with new calculations based on the valence-electron parametric potential method.