Radiative lifetime and transition probabilities in Cd I and Cd II

Radiative lifetimes of 11 levels belonging to the 5s5p ¹P^o₁, 5snd ³D_1,2 (n=6–9) and 5sns ³S₁ (n=7,8) series of Cd I, and of 5 levels of Cd II (i.e., 4d¹⁰5p ²P^o_1∕2,3∕2, 4d¹⁰6s ²S_1∕2, and 4d¹⁰5d ²D_3∕2,5∕2) have been measured using the time-resolved laser-induced fluorescence technique. Free neutral and singly ionized cadmium atoms have been generated by laser ablation. Single- or two-step excitation processes were considered to populate the levels under study. Branching fractions of Cd II transitions have been measured by laser-induced breakdown spectroscopy. Transition probabilities and oscillator strengths for Cd I and Cd II spectral lines originating from the above states as well as from the 4d⁹5s^2 2D_3∕2,5∕2 states of Cd II have been deduced by combining the experimental lifetimes and theoretical branching fractions obtained in multiconfigurational relativistic Hartree-Fock calculations taking core-polarization effects into account.