Measurement of the 145Sm half-life

The half-life of 145Sm has been measured by means of the reference source method with a HPGe detector. The long-lived radionuclide 44Ti was mixed into the source for reference. The time-dependency of the 145Sm/44Ti activity ratio was followed by assessing the count-rate ratio of their characteristic gamma-ray emissions at 61.2 keV (145Sm) and 67.9/78.3 keV (44Ti) in spectra recorded over periods of typically one day. In total, 220 measurements were performed over a period of 384 days or about one half-life period. The experiment and ensuing uncertainty budget are discussed in detail. Different error propagation is applied for random un-certainties, autocorrelated structures in the fit residuals, and potential systematic errors. The result for the 145Sm half-life, 345 (16) d, is compatible with the scarce literature values, however the experimental details of the old measurements were barely documented.

KAJAN Ivan;  POMME Stefaan;  PELCZAR Krzysztof;  HEINITZ Stephan; 

2021-10-19

PERGAMON-ELSEVIER SCIENCE LTD

JRC123974

0969-8043 (online),   

https://www.sciencedirect.com/science/article/pii/S0969804321003742,    https://publications.jrc.ec.europa.eu/repository/handle/JRC123974,   

10.1016/j.apradiso.2021.109978 (online),