title: PSA discriminator influence on (222)Rn efficiency detection in waters by liquid scintillation counting.
abstract: A procedure for the (222)Rn determination in aqueous samples using liquid scintillation counting (LSC) was evaluated and optimized. Measurements were performed by ultra-low background spectrometer Quantulus 1220™ equipped with PSA (Pulse Shape Analysis) circuit which discriminates alpha/beta spectra. Since calibration procedure is carried out with (226)Ra standard, which has both alpha and beta progenies, it is clear that PSA discriminator has vital importance in order to provide precise spectra separation. Improvement of calibration procedure was done through investigation of PSA discriminator level and, consequentially, the activity of (226)Ra calibration standard influence on (222)Rn efficiency detection. Quench effects on generated spectra i.e. determination of radon efficiency detection were also investigated with quench calibration curve obtained. Radon determination in waters based on modified procedure according to the activity of (226)Ra standard used, dependent on PSA setup, was evaluated with prepared (226)Ra solution samples and drinking water samples with assessment of measurement uncertainty variation included.
authors.affiliation: University of Novi Sad, Faculty of Technical Sciences, Novi Sad, Serbia.
authors.forename: Ivana
authors.initials: I
authors.lastname: Stojković
authors.affiliation: University of Novi Sad, Faculty of Sciences, Department of Physics, Novi Sad, Serbia.
authors.forename: Nataša
authors.initials: N
authors.lastname: Todorović
authors.affiliation: University of Novi Sad, Faculty of Sciences, Department of Physics, Novi Sad, Serbia.
authors.forename: Jovana
authors.initials: J
authors.lastname: Nikolov
authors.affiliation: University of Novi Sad, Faculty of Sciences, Department of Chemistry, Novi Sad, Serbia.
authors.forename: Branislava
authors.initials: B
authors.lastname: Tenjović
keywords: Calibration factor; Liquid scintillation counting; PSA discriminator; Radon measurements