High-Precision Half-life Measurement for the Superallowed Fermi $β^+$ Emitter ${}^{22}$Mg

Abstract

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

7 pages, 9 figures