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Primary standardization of Ra-224 activity by liquid scintillation counting
Published
Author(s)
Denis E. Bergeron, Jeffrey T. Cessna, Ryan P. Fitzgerald, Brian E. Zimmerman, Lizbeth Laureano-Perez, Ronald Colle, Leticia S. Pibida, Elisa Napoli
Abstract
A standard for 224Ra activity has been developed, based on triple-to-double coincidence ratio (TDCR) liquid scintillation (LS) counting. The standard was confirmed by efficiency tracing and 4παβ(LS)-γ(NaI(Tl)) anticoincidence counting, as well as by 4πγ ionization chamber and NaI(Tl) measurements. Secondary standard ionization chambers were calibrated with an expanded uncertainty of 0.57 % (k = 2). Calibration settings were also determined for a 5 mL flame- sealed ampoule on several commercial reentrant ionization chambers (dose calibrators).
Bergeron, D.
, Cessna, J.
, Fitzgerald, R.
, Zimmerman, B.
, Laureano-Perez, L.
, Colle, R.
, Pibida, L.
and Napoli, E.
(2019),
Primary standardization of Ra-224 activity by liquid scintillation counting, Applied Radiation and Isotopes, [online], https://doi.org/10.1016/j.apradiso.2019.108933
(Accessed October 14, 2025)