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Updated: Jun 27, 2025

Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh
Published on: May 3, 2019
Activity standard and calibrations for 227Th with ingrowing progeny
Denis E Bergeron1, Jeffrey T Cessna1, Brittany A Broder1
1Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
Abstract:
Thorium-227 was separated from its progeny and standardized for activity by the triple-to-double coincidence ratio (TDCR) method of liquid scintillation counting. Confirmatory liquid scintillation-based measurements were made using efficiency tracing with 3H and live-timed anticoincidence counting (LTAC). The separation time and the efficiency of the separation were confirmed by gamma-ray spectrometry. Calibrations for reentrant pressurized ionization chambers, including commercial radionuclide calibrators, and a well-type NaI(Tl) detector are discussed.

