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Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh
Published on: May 3, 2019
A note on the half-life of 209Po
R Collé1, Lizbeth Laureano-Perez, Iisa Outola
1Ionizing Radiation Division, Physics Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899-8462, USA. rcolle@nist.gov
Abstract:
The widely adopted value of (102+/-5)a for the (209)Po half-life, which is based on a single determination reported in 1956, appears to be in error by a large factor. Decay data from two separate primary standardizations of a (209)Po solution standard, conducted approximately 12 years apart, are inconsistent with the adopted value and its assigned uncertainty. An estimated half-life, larger than the adopted value by about 25%, is more consistent with the standardization data. A longer half-life is also supported by measurements on a recently standardized (210)Pb solution standard.
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