High-precision half-life determination of ${}^{14}$O via direct ${\hat{I}}^2$ counting

Abstract

The half-life of the superallowed Fermi $β^+$ emitter ${}^{14}$O was determined to high precision via a direct ${\hat{I}}^2$ counting experiment performed at the Isotope Separator and Accelerator (ISAC) facility at TRIUMF. The result, $T_{1/2}$(${}^{14}$O) = 70619.2(76) ms, is consistent with, but is more precise than, the world average obtained from 11 previous measurements. Combining the ${}^{14}$O half-life deduced in the present work with the previous most precise measurements of this quantity leads to a reduction in the overall uncertainty, by nearly a factor of 2. The new world average is $T_{1/2}$(${}^{14}$O) = 70619.6(63) ms with a reduced $\ddot{I}{‡}^2$ value of 0.87 obtained from 8 degrees of freedom.

8 pages, 6 figures, accepted for publication in the European Physical Journal A