72D/sub 3/2/-72D/sub 5/2/ excitation transfer in rubidium induced in collisions with ground-state Rb and noble-gas atoms

Cross sections for 72D/sub 3/2/bold-arrow-left-right72D/sub 5/2/ transfer in Rb, induced in collisions with He, Ne, Ar, and with ground-state Rb atoms, have been determined using methods of atomic fluorescence. Rb vapor, pure or mixed with a noble gas, was irradiated in a glass fluorescence cell with pulses of 660-nm radiation from a N2-laser-pumped dye laser, populating one of the 2D states by two-photon absorption. The resulting fluorescence included a direct component emitted in the decay of the optically excited state and a sensitized component arising from the collisionally populated state. Relative intensities of the components yielded the cross sections for 72D mixing: Q(2D/sub 3/2/→2D/sub 5/2/) = 8.8, 6.5, 10.4, and 30; Q(2D/sub 3/2/reverse arrow2D/sub 5/2/) = 5.8, 4.0, 6.9, and 18, in units of 10-14 cm2 for He, Ne, Ar, and Rb, respectively. Cross sections for the effective quenching of the 2D states were also determined