Corrections of Self-Absorption Effect Using the Monte Carlo Method in the Radioactivity Analysis of Environmental Samples
Seo, Bum-Kyoung;Lee, Dae-Won;Lee, Kil-Yong;Yoon, Yoon-Yeol;Yang, Tae-Keun;
ABSTRACT
In the low level radioactivity measurement, such as environmental radioactivity, there were used commonly cylindrical and Marinelli type beakers by means of measurement container. If there are differences in the matrix density or sample height between standard source and sample, it must be determined full energy peak efficiency considering self absorption effect. In this paper, we compared measured efficiency with calculated full energy peak efficiencies in the HPGe detector using the Monte Carlo method. For cylindrical container, we calculated the variation of the efficiency with sample height. Also, we calculated the variation of the detection efficiency with apparent density in the cylindrical and Marinelli container. It was seen that it need to be corrected for self absorption in the energy range of below 1000keV. Also, in order to verify the validity of calculation, we compared the calculated value with reference value using NIST SRM 4353 reference soil.