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Published on: May 3, 2019
Half-life and gamma-ray emission intensity measurements for 225Ac and progeny
Leticia Pibida1, Gulakhshan Hamad2, Denis E Bergeron1
1National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA.
Abstract:
The National Institute of Standards and Technology (NIST) performed new activity standardization measurements for 225Ac. As part of this work, the absolute photon emission intensities for the gamma-rays of 225Ac and progeny were determined using several high-purity germanium (HPGe) detectors. In addition, the half-life for 225Ac was determined using HPGe detectors, a well-type NaI(Tl) detector and micro-dose calibrator. Several measurement techniques were used to determine the source impurities that affect the half-life determination.
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