Absolute measurement of 192Ir

The radioactivity of 192Ir has been measured with several different techniques. The conventional 4πβ–γ coincidence results were confirmed by the 4πβ–γ(Ge) spectroscopic coincidence method, in which a large HPGe detector [120% cf. 3″×3″ NaI(Tl)] was used to avoid low γ-efficiency problems. A well-type NaI(Tl) crystal was applied for the 4πγ counting, which was very effective for such multi-γ emitting nuclides. These results were in good agreement, and those of preliminary relative measurements with ionization chambers and γ-spectrometry were also in reasonable agreement.