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Standardization of 237Np



Lizbeth Laureano-Perez, Ryan P. Fitzgerald, Ronald Colle


The standardization of 237Np was investigated. The certified massic activity for 237Np was obtained by 4 liquid scintillation (LS) counting with correction for the 233Pa daughter using the CIEMAT/NIST efficiency tracing method using a 3H standard. Confirmatory measurements were also performed by high-resolution HPGe gamma-ray spectrometry, and by 4(LS) - (NaI) anticoincidence counting. All results agree within the respective method’s uncertainties It was confirmed that the 237Np/233Pa radioactive equilibrium is disturbed when making dilutions and/or removing aliquots
Applied Radiation and Isotopes


anticoincidence counting, beta counting, CIEMAT/NIST method, efficiency tracing, liquid scintillation (LS), neptunium-237, radioactivity, SRM, standards


Laureano-Perez, L. , Fitzgerald, R. and Colle, R. (2013), Standardization of 237Np, Applied Radiation and Isotopes, [online], (Accessed April 19, 2024)
Created December 4, 2013, Updated November 10, 2018