Celik, Necati; Altin, Duygu; Cevik, Ugur

A new method was presented for the purpose of volumetric water content determination in any soil sample by gamma-ray transmission. Monte Carlo (MC) simulation technique was used to determine the functional behavior of the linear attenuation coefficient of soil samples having different water contents for three soil samples. Using this functional behavior, the linear attenuation coefficients of dry soil and water were obtained from the intercept and the slope, respectively. It was experimentally shown that the mass attenuation coefficients of soil samples were not sensitive to the chemical composition but only to the physical density. This independence was exploited in this study to obtain the linear attenuation coefficient of a completely dry soil which was found to be 0.1409, 0.1274, and 0.1657 cm−1 for Gumushane, Ardahan, and Trabzon soil, respectively. The linear attenuation coefficient of water was determined to be 0.09 cm−1. Then, the volumetric water contents were obtained by measuring the gamma-ray intensities passed through three wet soil samples. The results were found to be 0.186, 0.182, and 0.214 cm3 cm−3 for Gumushane, Ardahan, and Trabzon soil, respectively. The results obtained by the method introduced were compared with the results obtained using gravimetric method. A very good agreement was observed.

Celik, Necati; Altin, Duygu; Cevik, Ugur

In the presented study, a code was created for the purpose of true coincidence summing (TCS) correction factors for 134Cs. The created code was implemented in EGS4 Monte Carlo simulation package. TCS factors were determined for nine different energies for different detector-source geometries. The calculated results were successfully validated by an empirical method using a point 134Cs radioactive source and a p-type HPGe detector having 55% relative efficiency. Although the code created gives TCS factors only for 134Cs, the technique presented can be used to obtain the factors for any radionuclide used in gamma-ray spectrometry.