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Ronald Colle, Ryan P. Fitzgerald, Lizbeth Laureano-Perez
Abstract
A substantial 25 % error in the then known and accepted (102 5) year half-life of 209Po was reported on in 2007. This error was detected from decay data from two separate primary standardizations of a 209Po solution standard, which were performed approximately 12 years apart. Despite author claims that this observation was not a new half-life determination, it was nevertheless included in subsequent nuclear data evaluations and compilations to obtain a currently tabulated value of (115 13) a, computed from the median and range of the two half-life reports. A third primary standardization on the identical 209Po solution has since been performed to derive a new half-life value of (125.2 3.3) a. This half-life determination was obtained from 30 distinct data sets over a period of 20.7 years, encompassing over 700 liquid scintillation measurements with nearly 50 counting sources all prepared from the same solution, and as obtained over a very broad range of measurement conditions (composition of cocktails, characteristics of counters, time sequencing) during five periods in 1993, 1994, 2005, and 2013.
Colle, R.
, Fitzgerald, R.
and Laureano-Perez, L.
(2014),
The Half-Life of 209Po : Revisited, Journal of Physics G-Nuclear and Particle Physics, [online], https://doi.org/10.1088/0954-3899/41/10/105103
(Accessed October 20, 2025)