Determination of 93Zr decay scheme and half-life

This study describes a new determination of the decay scheme and half-life of 93Zr. A pure 93Zr solution was obtained after chemical separation from the dissolution of an irradiated zircaloy sample. The concentration of 93Zr in the solution was measured by mass spectrometry, with an isotopic dilution technique. The activity of the solution was measured by liquid scintillation counting, using an efficiency tracing method. The measurement of the activity concentration of 93Nbm by X-ray spectrometry, allowed the determination of the 93Zr decay scheme and the calculation of the 93Zr detection efficiency. This leads to the calculation of the decay probability of 93Zr toward 93Nbm of (0.73±0.06) and to a half-life of 93Zr of (1.64±0.06)×106 years. These values are discussed in comparison with the evaluated values available in the literature.