Open AccessStudy of the minimum detectable activity in gamma-ray spectrometry with various shielding configurations
Author(s) -
Vuong Quang Le,
Nguyen Hoang Vo,
Chuong Đinh Huynh,
Phuc Minh Lau,
Trung Quang Tran,
Tạo Văn Châu
Publication year - 2017
Publication title -
khoa học và công nghệ: tự nhiên
Language(s) - English
Resource type - Journals
ISSN - 2588-106X
DOI - 10.32508/stdjns.v1it4.496
Subject(s) - electromagnetic shielding , spectrometer , mass spectrometry , environmental radioactivity , radionuclide , gamma ray spectrometer , radiochemistry , gamma ray , gamma spectroscopy , nuclear physics , detector , physics , materials science , chemistry , optics , quantum mechanics
In the environmental radioactivity analyzing methods using gamma-ray spectrometry, the natural activities of radionuclides were required to be higher than the minimum detectable activity (MDA). To reduce MDA, one of the popular methods is to improve the ability of reducing the background radiation of the gamma-ray spectrometry. In this work, we designed the shielding configuration with 5 cm lead and 2 mm copper (thickness of walls and top). The MDAs of gamma-ray spectrometer were 2.6–4.24 times times for 40K (1460.8 keV), 232Th (208Tl- 2614.5 keV) and 238U (214Pb- 352 keV; 214Bi- 609.3 keV, 214Bi- 1764.5 keV). In the other hand, MDA for 238U with this shielding configuration is smaller than the activity of 238U inside surface soils in Vietnam. These results showed that the gamma spectrometer with NaI(Tl) detector and this shielding configuration was suitable for measurements activity of 238U in the environmental samples.