Determination of self-absorption corrections for gamma analysis of environmental samples: comparing gamma-absorption curves and spiked matrix-matched samples

Mass attenuation coefficients of soil and sediment samples using gamma energies from 46.5 to 1332 keV

“…The use of germanium detectors in high-resolution gamma spectrometry allows a precise quantitative determination of radionuclides in any type of environmental samples. In order to obtain accurate results, the sample should be counted with similar counting conditions of the calibrated system (Robu and Giovani, 2009;Debertin and Helmer, 1988;McMahon et al, 2004;Saegusa et al, 2004;Vargas et al, 2002). However, while most laboratories measuring environmental samples by gamma-ray spectrometry can prepare their samples in an essentially identical shape and size, they must contend with a large variety of sample densities and compositions (Al-Masri et al, 2010).…”

“…McMahon et al (2004) calculated the differences between the calculated linear attenuation coefficient and empirical values, which reached 15% at 59.5 keV of 241 Am, and 5e9% at higher energies. Maharewicz (2005) has established a relationship between self-attenuation correction factor of a cylindrical form of counting geometry and sample thickness (Equation (3).…”

Evaluation of Self-Attenuation Coefficients of Oil-Produced Scales for Gamma-Ray Spectroscopic Analysis

“…This loss of energy will result in diminution of c-rays reaching the detector and reducing the count rate observed under the photo-peak. [8][9][10] Self-absorption depends on several factors viz. material density, elemental composition, sample thickness, and the energy of the gamma-rays.…”

“…This method requires homogeneity tests which is too costly and time-consuming for laboratories that measure a wide variety of sample matrices. [8,13] The less time-consuming transmission method is determining the efficiency correction factors using aqueous calibration sources. This approach employs additional assumptions and approximations that will increase the measurement uncertainty.…”

Correction methodology for the spectral interfering γ-rays overlapping to the analytical peaks used in the analysis of 232Th

“…That is, if it is intended to perform the high-quality gamma spectrometric measurements, at least, the corrections for self-absorption effects for the measured g-rays with energy of generally below 300 keV, true coincidence summing (TCS) effects for the multi-cascading g-ray transitions, and the spectral gamma interferences to the analytical peaks must be taken into account in the used analytical procedures. Fortunately, there are numerous well-defined correction methods for the correction of TCS effects (Sudá r, 2002;DSM, 2005;Arnold and Sima, 2006;Dryá k and Ková r, 2009;Zhu et al, 2009;Yücel et al, 2009a) and self-absorption effects (ASTM E181, 2003;McMahon et al, 2004) from practical point of view. However, in literature survey, the methods relating to the estimation of the contributions from the interference peaks overlapping to the analytical peak of interest is still lacking or open to the investigation, which is important in view of obtaining more reliable peak area determinations.…”