title: Determination of gamma-ray self-attenuation correction in environmental samples by combining transmission measurements and Monte Carlo simulations.
abstract: We develop a simple and widely applicable method for determining the self-attenuation correction in gamma-ray spectrometry on environmental samples. The method relies on measurements of the transmission of photons over the matrices of a calibration standard and an analysed sample. Results of this experiment are used in subsequent Monte Carlo simulations in which we first determine the linear attenuation coefficients (μ) of the two matrices and then the self-attenuation correction for the analysed sample. The method is validated by reproducing, over a wide energy range, the literature data for the μ of water. We demonstrate the use of the method on a sample of sand, for which we find that the correction is considerable below ~400keV, where many naturally occurring radionuclides emit gamma rays. At the lowest inspected energy (~60keV), one measures an activity that is by a factor of ~1.8 smaller than its true value.
authors.affiliation: Institute for Medical Research and Occupational Health, Ksaverska cesta 2, HR-10001 Zagreb, Croatia. Electronic address: msostaric@imi.hr.
authors.forename: Marko
authors.initials: M
authors.lastname: Šoštarić
authors.affiliation: Institute for Medical Research and Occupational Health, Ksaverska cesta 2, HR-10001 Zagreb, Croatia. Electronic address: dbabic@imi.hr.
authors.forename: Dinko
authors.initials: D
authors.lastname: Babić
authors.affiliation: Institute for Medical Research and Occupational Health, Ksaverska cesta 2, HR-10001 Zagreb, Croatia. Electronic address: petrinec@imi.hr.
authors.forename: Branko
authors.initials: B
authors.lastname: Petrinec
authors.affiliation: Department of General Agronomy, Faculty of Agriculture, University of Zagreb, Svetošimunska cesta 25, HR-10000 Zagreb, Croatia. Electronic address: zzgorelec@agr.hr.
authors.forename: Željka
authors.initials: Ž
authors.lastname: Zgorelec
mesh_terms: D002138:Calibration; D003198:Computer Simulation; D004784:Environmental Monitoring / Q000706:statistics & numerical data*; D005720:Gamma Rays; D006801:Humans; D009010:Monte Carlo Method; D011834:Radiation Monitoring / Q000706:statistics & numerical data*; D011868:Radioisotopes / Q000032:analysis; D013051:Spectrometry, Gamma / Q000706:statistics & numerical data*
chemical_list: D011868:Radioisotopes
keywords: Gamma-ray spectrometry; Linear attenuation coefficient; Monte Carlo simulation; Self-attenuation correction