Measurements and calculations of metastable level lifetimes in Fe X, Fe XI, Fe XII, Fe XIII, and Fe XIV - art. no. 032515

Lifetimes of metastable levels in the ground term of Fe ions within the 3s( 2)3p(k), k=1-5, isoelectronic sequences have been measured. These measureme nts were performed utilizing ions that were selected by mass to charge rati o while transported from an electron cyclotron resonance ion source to a Ki ngdon ion trap, where they were captured and then confined for periods of u p to 2.1 s. During this storage period, selected emission wavelengths of tr ansitions from metastable levels in the visible or near-ultraviolet spectra l regions were isolated using interference filters, and the time-dependent fluorescence intensities were measured using a photomultiplier tube. Measur ement precisions on the order of 2% were achieved in favorable cases. The m easured lifetimes are tau (Fe x, 3s(2)p(5) P-2(1/2)) = 13.64+/-0.25 ms, tau (Fe XI, 3s(2)3p(4 1)D(2)) = 9.86+/-0.22 ms, tau (Fe XII, 3s(2)3p(3) P-2(3/ 2)) = 1.85+/-0.24 ms, tau (Fe XII, 3s(2)3p(3) P-2(1/2)) = 4.38+/-0.42 ms, t au (Fe XII, 3s(2)3p(3) D-2(3/2)) = 20.35 +/-1.24 ms, tau (Fe XIII, 3s(2)3p( 2) D-1(2)) = 6.93+/-0.18 ms, and tau (Fe XIV, 3s(2)3p P-2(3/2)) = 17.52+/-0 .29 ms. These results are compared with existing and with new theoretical c alculations, which have estimated uncertainties on the order of 10-25%.