Determination of half-life and photon emission probabilities of 65Zn

A 65Zn radioactive solution standardized by an absolute measurement method at Laboratoire National Henri Becquerel (LNHB), was sent to Bureau International des Poids et Mesures (BIPM), in order to include the results in their database. The activity value determined at BIPM was in good agreement with that stated by LNHB (the difference was 0.3%). Additional measurements of 65Zn activity and half-life were also carried out, by using a 4πγ ionization chamber; the half-life value proposed by this work: 244.15 (10) days, is consistent to others reported in the literature. The spectra analysis was performed by γ-ray spectrometry with high-purity germanium detectors, with the aim to improve the accuracy of the photon emission probabilities values of this nuclide. The determined photon emission probabilities are 0.498 for the 1115 keV γ-ray, 0.347 and 0.0479 for the X-rays Cu-Kα and Cu-Kβ; the associated uncertainties are 0.4%, 0.9% and 1.1%, respectively.