Collisional quenching and j-mixing rate constants for the 3D levels of Ca+

Collisional relaxation and fine-structure mixing rate constants have been measured for the metastable D doubler (30(3/2), 30(5/2)) of Ca+ ions in the presence of different neutral gases completing a previous work. Experimental results are given for He, Ne, Ar, H-2, N-2, and CH4,. These data have been obtained with a cloud of approximately 10(5) Ca+ ions stored in a Paul trap at kinetic energies of around 1 eV. The investigated levels were populated by direct excitation of the corresponding 4S-3D transitions. The involved time constants were determined from the temporal evolution of the fluorescence of one of the resonance transitions, following the optical pumping of the P level from the D component. Comparison of our data with other similar experimental and theoretical work is finally presented.