title: Analysis of thorium and its progeny by gamma ray spectrometry and alpha track methods.
abstract: Samples originating from an EU sponsored intercomparison exercise were analysed by gamma ray spectrometry (a thorium solution sample, a zircon sand sample and a thorium ore sample). An alpha track method was also used to analyse the solution sample. The detection efficiency calibration for the gamma ray spectrometry measurements on the solid samples was established using an in-house standard of thorium nitrate. A GESPECOR Monte Carlo simulation program was utilised in the analysis of the solution sample. The in-house thorium nitrate standard was also used to prepare standards for the alpha track method. The relative differences between the 232Th activity concentration values determined in these intercomparison samples and values supplied by the NPL, UK, were found to be less than 5% when determined by the gamma ray spectrometry method and less than 8% when determined by the alpha track method.
authors.affiliation: Horia Hulubei National Institute of Physics and Nuclear Engineering, Bucharest, Romania. greta@ifin.nipne.ro
authors.forename: L
authors.initials: L
authors.lastname: Dinescu
authors.forename: O
authors.initials: O
authors.lastname: Sima
authors.forename: A
authors.initials: A
authors.lastname: Danis
authors.forename: M
authors.initials: M
authors.lastname: Ciubotariu
authors.forename: E M
authors.initials: EM
authors.lastname: Cincu
authors.forename: D
authors.initials: D
authors.lastname: Matei
mesh_terms: D000512:Alpha Particles; D005720:Gamma Rays; D011874:Radiometry / Q000379:methods*; D017640:Silicates / Q000032:analysis; D013051:Spectrometry, Gamma / Q000379:methods*; D013910:Thorium / Q000032:analysis*; D017970:Thorium Compounds / Q000032:analysis; D015040:Zirconium / Q000032:analysis
chemical_list: D017640:Silicates; D017970:Thorium Compounds; C003784:zircon; D013910:Thorium; D015040:Zirconium; C036680:thorium nitrate