Direct Measurement of Radiative Lifetimes of Excited States in Refractory-Metal Atoms Using a Sputtering Technique

A new technique is reported for measuring atomic lifetimes in uranium and other refractory metals. Selective excitation of low-lying levels in neutral atoms can be obtained by means of a fast heavy-ion-induced sputtering. By pulsing the ion beam, the lifetimes of the 16 900- and 19 885-cm^-1 levels in neutral uranium have been determined by the delayed-coincidence technique to be 232±{}25 and 142±{}15 ns, respectively. New lifetime determinations in ZrI are also reported.