Revision of nuclear data of 235U and 226Ra for the 186-keV gamma-ray peak for the determination of activity in environmental samples
In this work, the ratio contribution of 226Ra and 235U in γ spectra with the latest update nuclear data will be revised. The results showed that in the total count rate of the 186 keV peak consists of 57.2% of 226Ra (186.2 keV) and 42.8% of 235U (185.7 keV) with the existence of equilibrium. These calculations were used for determining mass activity of 238U for the direct and fast measurement using only the 186 keV peak and verifying the 238U–226Ra secular equilibrium. An equilibrium method was measured secular equilibrium of decay chain 238U (by the product daughter 214Bi-609.3 keV) that was used for this study. The maximum relative deviation was less than 4.0% between both methods proved the direct method was reliable and can be applied to determine the mass activity of 238U in the radioactive equilibrium samples.
KeywordsDirect method Equilibrium method Secular equilibrium Gamma spectrometry
This research is funded by Vietnam National University Ho Chi Minh City under Grant Number B2017-18-02.
- 1.Corte FD, Umans H, Vandenberghe D, Wispelaere AD, Van den Haute P (2005) Direct gamma-spectrometric measurement of the 226Ra 186.2 keV line for detecting 238U/226Ra disequilibrium in determining the environmental dose rate for the luminescence dating of sediments. Appl Radiat Isot 63:589–598CrossRefGoogle Scholar
- 2.Ebaid YY (2010) Use of gamma-ray spectrometry for uranium isotopic analysis in environmental samples. Rom J Phys 55:69–74Google Scholar
- 9.http://www.nucleide.org/Laraweb/. Accessed 28 July 2017
- 10.GUM (2008) Evaluation of measurement data—introduction to the “Guide to the expression of uncertainty in measurement” and related document. BIPM. http://www.bipm.org
- 11.Lépy MC, Ferreux L, Hamon C, Plagnard J (2008) Logicised d’ajustement des courbes de rendement ACORES. Note tech. LNHB 2008-2045Google Scholar
- 12.Lépy MC (2004) Presentation of the COLEGRAM software. Note tech. LNHB 04/26Google Scholar
- 13.Rangaswamy DR, Srilatha MC, Ningappa C, Srinivasa E, Sannappa J (2016) Measurement of natural radioactivity and radiation hazards assessment in rock samples of Ramanagara and Tumkur Districts, Karnataka, India. Environ Earth Sci 75:373 (1–11)Google Scholar