Comparison of simulated and experimental values of self-absorption correction factors for a fast and credible adjust in efficiency curve of gamma spectroscopy. (November 2018)

• Record Type: Journal Article
• Authors: Lopes, J.M.; Medeiros, M.P.C.; Garcêz, R.W.D.; Filgueiras, R.A.; Thalhofer, J.L.; Silva Júnior, W.F.R.; Silva, A.X.
• Is Part Of: Applied radiation and isotopes. Volume 141(2018:Nov.)
• Page Start: 241
• Page End: 245
• Publication Date: 2018-11
• Subjects: Gamma spectroscopy -- Self-absorption -- MCNPX -- LabSOCS; Radiology -- Periodicals; Radiation -- Industrial applications -- Periodicals; Nuclear chemistry -- Periodicals; Internet resource; Periodical; 660.298
• DOI: 10.1016/j.apradiso.2018.05.005
• Languages: English
• ISSNs: 0969-8043

Abstract

Abstract: Self-absorption correction factors are fundamental in spectroscopy to correct the efficiency of the samples detection whose density is different from the radioactive standard. Mathematical simulations have been widespread as a tool to facilitate the procedure of correction factors calculation. In this paper, LabSOCS was used to calculate the self-absorption correction factor for some geometries and the values found were compared to those obtained in MCNP and experimental values. The percentage deviations found for the self-absorption correction factor calculated by LabSOCS were below 1.6% when compared to experimental values. Deviations were below 1.9% in the curve extrapolation of the experimental procedure found in literature. Results obtained show that the deviations increase proportionally to the difference between the density values of the radioactive standard and the sample. High percentage deviations were also noticed in simulations whose samples had high densities, complex geometries and low energy gamma-rays. Highlights: Great density differences between the sample and the radioactive standard should not be used. It is noticed that percentage deviations increase with an increase in density and with an energy decrease. Geometry complexity is a factor which increases the percentage differences of the self-absorption correction factor. Must be careful when reproducing the same chemical compositions of the experimental procedure in a computational simulation.