State-of-the-art signal digitization and analysis techniques have been used to measure the half-life of the Fermi $\beta$ decay of ${}^{26}$Al${}^m$. The half-life was determined to be 6347.8 $\pm$ 2.5 ms. This new datum contributes to the experimental testing of the conserved-vector-current hypothesis and the required unitarity of the Cabibbo-Kobayashi-Maskawa matrix: two essential components of the standard model. Detailed discussion of the experimental techniques and data analysis and a thorough investigation of the statistical and systematic uncertainties are presented.

• Received 11 July 2010

DOI:https://doi.org/10.1103/PhysRevC.84.024611