High Precision Measurements Of Na-26 Beta(-) Decay

High-precision measurements of the half-life and beta-branching ratios for the beta(-) decay of Na-26 to Mg-26 have been measured in beta-counting and gamma-decay experiments, respectively. A 4 pi proportional counter and fast tape transport system were employed for the half-life measurement, whereas the gamma rays emitted by the daughter nucleus Mg-26 were detected with the 8 pi gamma-ray spectrometer, both located at TRIUMF's isotope separator and accelerator radioactive beam facility. The half-life of Na-26 was determined to be T-1/2=1.07128 +/- 0.00013 +/- 0.00021 s, where the first error is statistical and the second systematic. The logft values derived from these experiments are compared with theoretical values from a full sd-shell model calculation.