High-precision half-life determination of 14O via direct β counting.

The half-life of the superallowed Fermi β + emitter 14 O was determined to high precision via a direct β 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 χ 2 value of 0.87 obtained from 8 degrees of freedom. [ABSTRACT FROM AUTHOR]