High-precision half-life measurement for the superallowed Fermi β+ emitter Mg22

A high-precision half-life measurement for the superallowed Fermi ${\ensuremath{\beta}}^{+}$ emitter $^{22}\mathrm{Mg}$ was performed at the TRIUMF-ISAC facility using a $4\ensuremath{\pi}$ proportional gas counter. The result of ${T}_{1/2}=3.87400\ifmmode\pm\else\textpm\fi{}0.00079$ s is a factor of 3 more precise than the previously adopted world average and resolves a discrepancy between the two previously published $^{22}\mathrm{Mg}$ half-life measurements.