title: Analysis of161Tb by radiochemical separation and liquid scintillation counting.
abstract: The determination of161Tb activity is problematic due to its very low fission yield, short half-life, and the complication of its gamma spectrum. At AWE, radiochemically purified161Tb solution was measured on a PerkinElmer 1220 QuantulusTMLiquid Scintillation Spectrometer. Since there was no161Tb certified standard solution available commercially, the counting efficiency was determined by the CIEMAT/NIST Efficiency Tracing method. The method was validated during a recent inter-laboratory comparison exercise involving the analysis of a uranium sample irradiated with thermal neutrons. The measured161Tb result was in excellent agreement with the result using gamma spectrometry and the result obtained by Pacific Northwest National Laboratory.
authors.affiliation: AWE plc, Aldermaston, Reading RG7 4PR, UK. Electronic address: jun.jiang@awe.co.uk.
authors.forename: J
authors.initials: J
authors.lastname: Jiang
authors.affiliation: AWE plc, Aldermaston, Reading RG7 4PR, UK.
authors.forename: A
authors.initials: A
authors.lastname: Davies
authors.affiliation: Pacific Northwest National Laboratory, 902 Battelle Boulevard, P.O. Box 999, MSIN J4-65, Richland, WA 99352, USA.
authors.forename: L
authors.initials: L
authors.lastname: Arrigo
authors.affiliation: Pacific Northwest National Laboratory, 902 Battelle Boulevard, P.O. Box 999, MSIN J4-65, Richland, WA 99352, USA.
authors.forename: J
authors.initials: J
authors.lastname: Friese
authors.affiliation: Pacific Northwest National Laboratory, 902 Battelle Boulevard, P.O. Box 999, MSIN J4-65, Richland, WA 99352, USA.
authors.forename: B N
authors.initials: BN
authors.lastname: Seiner
authors.affiliation: Pacific Northwest National Laboratory, 902 Battelle Boulevard, P.O. Box 999, MSIN J4-65, Richland, WA 99352, USA.
authors.forename: L
authors.initials: L
authors.lastname: Greenwood
authors.affiliation: Pacific Northwest National Laboratory, 902 Battelle Boulevard, P.O. Box 999, MSIN J4-65, Richland, WA 99352, USA.
authors.forename: Z
authors.initials: Z
authors.lastname: Finch
keywords: CIEMAT/NIST method; Eichrom® LN Resin; Liquid scintillation counting; Terbium-161