Izvestiya vuzov. Yadernaya Energetika

The peer-reviewed scientific and technology journal. ISSN: 0204-3327

Proliferation Protection of Uranium Due to the Presence of 232U Decay Products as Intense Sources of Hard Gamma Radiation

1/20/2022 2022 - #01 Physics in nuclear power engineering

Kulikov G.G. Shmelev A.N. Apse V.A. Kulikov E.G.

DOI: https://doi.org/10.26583/npe.2022.1.12

UDC: 621.039.58

The purpose of the article is to show the nuclear-physical causes of hard γ-quanta in the uranium-232 decay chain, to propose tactics for handling uranium containing uranium-232, and to assess the magnitude of its protective γ-barrier against uncontrolled use of uranium.

The authors show the general picture of the decays of the chain of nuclide transformations of uranium-232, on which the protection of uranium from its uncontrolled use is based. During the decay of nuclei, their emission of α- or β-particles is only the first stage of the most complex process of rearrangement of both the internal structure of the nucleus itself, which consists in the rearrangement of the neutron and proton shells and the levels of its excitation, and in the rearrangement of the electron shells of the atom. As a rule, the daughter nucleus is in a highly excited state, which is removed by the emission of hard γ-quanta and internal conversion electrons. After the second case, the remaining excitation of the atom is removed by the emission of characteristic γ-quanta and Auger-electrons with characteristic γ -quanta.

In addition, explanations are given for the quantum-mechanical reasons for the hard γ-radiation of thallium-208 and bismuth-212, which complete the decay chain of uranium-232.

The authors also proposed a tactic for handling uranium containing uranium-232. Since the hard γ-quanta of thallium-208 and bismuth-212 appear only at the end of the decay chain of uranium-232, after its chemical purification from its decay products, uranium-232 itself does not pose a radiation hazard; therefore, at this time it is advisable to conduct all necessary operations for transporting the material to the plant, fabricating uranium-based fuel containing uranium-232, and transporting this fuel to the nuclear facility where it will be used.


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hard γ-radiation chain of nuclide transformations of uranium-232 proliferation protection of uranium

Link for citing the article: Kulikov G.G., Shmelev A.N., Apse V.A., Kulikov E.G. Proliferation Protection of Uranium Due to the Presence of 232U Decay Products as Intense Sources of Hard Gamma Radiation. Izvestiya vuzov. Yadernaya Energetika. 2022, no. 1, pp. 140-150; DOI: https://doi.org/10.26583/npe.2022.1.12 (in Russian).