title: Determination of disintegration rates and gamma-ray emission probabilities of 65Zn and 241Am.
abstract: Radioactive solutions of (65)Zn and (241)Am were standardized within the frame of the CCRI (II)/BIPM key comparisons carried out recently in 2003. The activity concentrations (in Bqg(-1)) were determined using the 4pi(proportional counter)-gamma coincidence counting method with efficiency extrapolation. Liquid scintillation methods were also used for (241)Am activity determination. The 1115.5 keV of (65)Zn and the 26.35 and 59.54 keV of (241)Am gamma-ray emission probabilities were determined as 0.4971, 0.0206 and 0.3587, respectively, using a planar germanium detector. The associated relative uncertainties were 0.33%, 1.56% and 0.47%, respectively.
authors.affiliation: Laboratório Nacional de Metrologia das Radiações Ionizantes, Instituto de Radiprotecao e, Ionizantes Instituto Radioprotecao, Dosimetria (LNMRI/IRD/CNEN), Av. Salvador Allende, s/n, Recreio, CEP 22780-160, Rio de Janeiro, Brazil. iwahara@ird.gov.br
authors.forename: Akira
authors.initials: A
authors.lastname: Iwahara
authors.forename: Mônica
authors.initials: M
authors.lastname: Aguiar Leobino da Silva
authors.forename: Antônio
authors.initials: A
authors.lastname: Edsom Carvalho Filho
authors.forename: Estela Maria de Oliveira
authors.initials: EM
authors.lastname: Bernardes
authors.forename: José Ubiratan
authors.initials: JU
authors.lastname: Delgado