Determination of the half-life of 161Tb. (March 2023)

• Record Type: Journal Article
• Authors: Dong, Jiangpeng; Bai, Tao; Hu, Yaowen; Zhang, Xiangbo; Fan, Jinlong; Dai, Yihua; Miao, Liangliang; Yu, Xiaoren; Li, Zhiming
• Is Part Of: Applied radiation and isotopes. Volume 193(2023)
• Publication Date: 2023-03
• Subjects: 161Tb -- Half-life -- Gamma ray spectrometry -- Uncertainty budget; Radiology -- Periodicals; Radiation -- Industrial applications -- Periodicals; Nuclear chemistry -- Periodicals; Internet resource; Periodical; 660.298
• DOI: 10.1016/j.apradiso.2022.110647
• Languages: English
• ISSNs: 0969-8043

Abstract

Abstract: 161 Tb has potential applications in targeted radionuclide therapy and nuclear forensic science. However, the half-lives of 161 Tb in previous studies show a discrepancy. In this study, 161 Tb samples were produced by irradiating 160 Gd2 O3 with thermal neutron flux. A series of procedures were applied to extract a pure 161 Tb solution and three solid samples were prepared. The half-life of 161 Tb has been measured with a high-purity germanium (HPGe) detector. The time-dependency of the 161 Tb activity was followed by assessing the count rate of their characteristic gamma-ray emissions at 48.9 keV and 74.6 keV over a period of 33–43 days. The experiment and uncertainty budget are discussed in detail. Different uncertainty propagation equations were applied for random uncertainties, medium-frequency deviations and potential systematic errors. The result for the 161 Tb half-life of 6.967 (11) d was determined by the weighted mean of half-lives from three samples, which confirms that the half-life is longer than the of the current evaluated half-life of 6.89 (2) d. From all available quoted experimental values, a recommended half-life of 6.934 (14) d was determined by the power-moderated method (PMM). Based on recent four published half-life values, a half-life of 161 Tb of 6.9582 (33) d was determined by the PMM analysis. Highlights: The new half-life value of 6.967 (11) d for 161 Tb has been determined. The half-life determined in this work has a relative standard uncertainty of 0.17%. A revised value of T 1/2 ( 161 Tb) = 6.934 (14) d was determined by the power-moderated mean method.