Lifetime measurements in CeI, CeII, and CeIII using time-resolved laser spectroscopy with application to stellar abundance determinations of cerium -art. no. 032505

Radiative lifetimes of two levels in Ce I, eight levels in Ce rr, and nine levels in Ce III have been measured using the time-resolved laser-induced f luorescence technique. Free cerium atoms and singly and doubly ionized ions were obtained in a laser-produced plasma. A narrow bandwidth UV laser puls e was employed to selectively populate the short-lived upper levels and the lifetime values were evaluated from the time-resolved fluorescence signals recorded by a fast detection system. Transition probabilities for Ce III w ere obtained from branching fractions calculated by the Cowan code and the experimental lifetimes. The results are compared with previous measurements and calculations. Spectral Lines of Ce III were identified in the spectrum of the magnetic chemically peculiar star alpha(2)CVn and the abundance of cerium was determined from synthetic spectrum fitting to be 800 times great er than the solar abundance.