title: Activity standardization by liquid scintillation counting and half-life measurements of 90Y.
abstract: Radioactive 90Y was standardized by means of 4piBeta liquid scintillation efficiency tracing with a two-phototube counting system. The efficiencies of 90Y and the tracer 3H are related by the CIEMAT/NIST method. The dependence of the calculated efficiency on various shape factors and the importance of accurately measuring the radionuclide impurity of 90Sr are discussed. The half-life of 90Y was measured with improved accuracy by means of a liquid scintillation counting and a 4pi ionization chamber measuring system, and an average value T1/2 = 64.053(20) h was found.
authors.affiliation: Department 6.1, Physikalisch-Technische Bundesanstalt, Bundesallee 100, Braunschweig D-38116, Germany. Karsten.Kossert@ptb.de
authors.forename: K
authors.initials: K
authors.lastname: Kossert
authors.forename: H
authors.initials: H
authors.lastname: Schrader
mesh_terms: D006207:Half-Life; D016018:Least-Squares Analysis; D015203:Reproducibility of Results; D012588:Scintillation Counting / Q000379:methods; D012680:Sensitivity and Specificity; D015021:Yttrium Radioisotopes / Q000032:analysis / Q000592:standards*
chemical_list: D015021:Yttrium Radioisotopes