Precision and accuracy of lifetimes of metastable levels using the Kingdontrap technique

The accuracy of measurements of the lifetimes of metastable levels using a Kingdon ion trap technique is discussed with reference to the recent measur ement of the transition rate from the excited 2s2p P-3(2) level of AR XV. P articular attention focused on the aspects of the Kingdon trap technique, w hich differed from competing alternatives and might apply differently to gr ound and excited terms. These differences are related to the corrections fo r quenching of the metastable level by ion-atom collisions, to the possible quenching by Stark mixing due to the higher electric field of the Kingdon trap, and to optical effects associated with the charging of a lens in the light collection system. No significant systematic corrections to present e xcited level measurements were identified. (C) 1999 Elsevier Science B.V.