Evaluation of Natural Radioactivity Levels for Structural Material Used in the Construction of the Neutrino Detector

Vladimir G. Zinovyev^*, Anatolii P. Serebrov, Ivan A. Mitropolsky, Yuriy E. Loginov, Georgiy I. Shulyak, Tatyana M. Tyukavina, Sergey L. Sakharov, Anatoly V. Chernyj

Neutron Research Department, National Research Centre “Kurchatov Institute”, B.P. Konstantinov Petersburg Nuclear Physics Institute, Gatchina, Russia.

DOI: 10.4236/wjnst.2015.51005                

Abstract

In this work, the evaluation of natural radioactivity and spontaneous fission rates was performed for 8 nuclides from the natural radioactive ²³⁸U, ²³⁵U and ²³²Th decay chains. For this purpose, three samples of structural materials of the neutrino detector, i.e. aluminum, titanium and glass were analyzed by gamma spectroscopy and by neutron activation analysis to quantify a specific radioactivity of the samples. According to the results of this investigation, glass and aluminum samples have maximum values of the mean uranium concentrations 7.3(7) × 10^-4% and 3.1(6) × 10^-5%, respectively, while the lowest value for mean concentration of the uranium was found in titanium samples to be 4.7(3) × 10^-6%. Aluminum sample had maximum values of the mean thorium concentrations, 2.5(8) × 10^-3%, while the lowest value for mean concentration of the thorium was found in titanium samples to be 6.2(3) × 10^-7%.

Keywords

Spontaneous Fission, Radioactive Decay Chain, α-Decay, Radionuclide, Branching Factor

Conflicts of Interest

The authors declare no conflicts of interest.

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