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Published on: May 3, 2019
Standardization of (166m)Ho and 243Am/239Np by live-timed anti-coincidence counting with extending dead time
C J da Silva1, J S Loureiro, J U Delgado
1Laboratório Nacional de Metrologia das Radiações Ionizantes (LNMRI), Instituto de Radioproteção e Dosimetria (IRD), Comissão Nacional de Energia Nuclear (CNEN), Av. Salvador Allende, s/n(o) - Recreio, CEP 22780-160, Rio de Janeiro, Brazil. Carlos@ird.gov.br
Abstract:
The National Laboratory for Metrology of Ionizing Radiation (LNMRI)/Brazil acquired (166m)Ho and (243)Am/(239)Np solutions from commercial suppliers in order to realize primary standardization and therefore reducing the associated uncertainties. The method used in the standardization was the live-timed 4πβ(LS)-γ(ΝaI(Tl)) anticoincidence counting. The live-timed anticoincidence system is operated since 2006 in LNMRI and is composed of two MTR2 modules donated by Laboratoire National Henri Becquerel (LNE-LNHB)/France. The data acquisition system uses a homemade LabView program and an Excel file for calculus. These systems have been used for primary standardization at LNMRI for many radionuclides and recently took part in the (124)Sb and (177)Lu International Key Comparisons with good performance.
