Precise intercombination transition rates in C+ and N2+ ions measured at aheavy-ion storage ring

The slow electric dipole intercombination decay of the 2s2p(2) P-4(J) level s in the B-like ions C+ and N2+ has been optically observed from ions circu lating in a storage ring. The lifetime results are (7.95 +/- 0.07, 104.1 +/ - 0.5, 22.05 +/- 0.07) ms for the J = 1/2, 3/2 and 5/2 levels in C+, and (1 .32 +/- 0.05, 13.9 +/- 0.2, 3.30 +/- 0.07) ms for the game levels in N2+, r espectively. This represents an improvement in precision by a factor of up to 10 compared to previous experimental results. The observed lifetime patt ern is consistent with a number of theoretical predictions, removing discre pancies between experiment and theory that had been claimed previously.