title: Standardization of 241Am by digital coincidence counting, liquid scintillation counting and defined solid angle counting.
abstract: The nuclide (241)Am decays by alpha emission to (237)Np. Most of the decays (84.6%) populate the excited level of (237)Np with energy of 59.54 keV. Digital coincidence counting was applied to standardize a solution of (241)Am by alpha-gamma coincidence counting with efficiency extrapolation. Electronic discrimination was implemented with a pressurized proportional counter and the results were compared with two other independent techniques: Liquid scintillation counting using the logical sum of double coincidences in a TDCR array and defined solid angle counting taking into account activity inhomogeneity in the active deposit. The results show consistency between the three methods within a limit of a 0.3%. An ampoule of this solution will be sent to the International Reference System (SIR) during 2009. Uncertainties were analysed and compared in detail for the three applied methods.
authors.affiliation: Laboratorio de Metrología de Radioisótopos, CNEA, Buenos Aires, Argentina. balpardo@cae.cnea.gov.ar
authors.forename: C
authors.initials: C
authors.lastname: Balpardo
authors.forename: M E
authors.initials: ME
authors.lastname: Capoulat
authors.forename: D
authors.initials: D
authors.lastname: Rodrigues
authors.forename: P
authors.initials: P
authors.lastname: Arenillas
mesh_terms: D000512:Alpha Particles; D000576:Americium / Q000592:standards*; D007391:International Cooperation; D011874:Radiometry / Q000379:methods*; D012015:Reference Standards; D015203:Reproducibility of Results; D012588:Scintillation Counting / Q000379:methods; D035501:Uncertainty
chemical_list: D000576:Americium