감마선 스펙트럼 비율을 이용한 매립 선원의 깊이 평가 방법론 개발 연구

• 영문명: Study on Development of Embedded Source Depth Assessment Method Using Gamma Spectrum Ratio
• 발행기관: 한국방사성폐기물학회
• 저자명: 김준하 정재학 홍상범 서범경 이병채
• 간행물 정보: 『Journal of Nuclear Fuel Cycle and Waste Technology (JNFCWT)』Vol.18 No.1, 51~62쪽, 전체 12쪽
• 주제분류: 공학 > 공학일반
• 파일형태: PDF
• 발행일자: 2020.03.30

국문 초록

This study was conducted to develop a method for depth assessment of embedded sources using gamma-spectrum ratio and for the evaluation of field applicability. To this end, Peak to Compton and Peak to valley ratio changes were evaluated according to 137Cs, 60Co, 152Eu point source depth using HPGe detector and MCNP simulation. The effects of measurement distance of PTV and PTC methods were evaluated. Using the results, the source depth assessment equation using the PTC and PTV methods was derived based on the detection distance of 50 cm. In addition, the sensitivity of detection distance changes was assessed when using PTV and PTC methods, and error increased by 3 to 4 cm when detection distance decreased by 20 cm based on 50 cm. However, it was confirmed that if the detection distance was increased to 100 cm, the effects of detection distance were small. And PTV and PTC methods were compared with the two distance measurement method which evaluates the depth of source by the change of net peak counting rate according to the detection distance. As a result of source depth assessment, the PTV and PTC showed a maximum error of 1.87 cm and the two distance measurement method showed maximum error of 2.69 cm. The results of the experiment confirmed that the accuracy of the PTV and PTC methods was higher than two distance measurement. In addition, Sensitivity evaluation by horizontal position error of source has maximum error of less than 25.59 cm for the two distance measurement method. On the other hand, PTV and PTC method showed high accuracy with maximum error of less than 8.04 cm. In addition, the PTC method has lowest standard deviation for the same time measurement, which is expected to enable rapid measurement.

키워드

HPGe detector In-situ measurement Hotspot Source depth Peak to Compton Peak to Valley