Measurement of the 177Lu half-life

The half-life of (177)Lu was measured by following the decay of sources with an ionisation chamber and with a liquid scintillation counter over a period of 85 and 42 days, respectively. The detector signals showed three major components: decay of (177)Lu, decay of (177m)Lu and the background signal. The half-life value, T(1/2)((177)Lu)=6.6465 (50)d, was obtained by a least-squares fit of two exponential decay functions and a constant background to the experimental data. The data was corrected for decay during the measurements. Residuals of the fit and uncertainty budgets are presented in this paper. The result is in agreement with three out of seven previously published measurement results and the currently recommended value of 6.647 (4) d (Kondev, 2002). A new value of T(1/2)((177)Lu)=6.6465 (32) d was obtained from a weighted mean of our results with the selected literature data.