FIGURE 2.1. Graphical depiction of the Mo-99 decay chain.

FIGURE 2.1Graphical depiction of the Mo-99 decay chain

Mo-99 decays by emitting a beta particle (an electron). About 88 percent of the decays (red line) produce Tc-99m, which subsequently decays to the ground state, Tc-99g, by emitting a gamma ray. About 12 percent of the decays (blue line) produce Tc-99g directly. Tc-99g decays to stable (i.e., nonradioactive) ruthenium-99 (Ru-99) after emitting a beta particle. The half-lives for these decay processes are shown on the diagram.

From: 2, Medical Isotope Production and Utilization

Cover of Molybdenum-99 for Medical Imaging
Molybdenum-99 for Medical Imaging.
Committee on State of Molybdenum-99 Production and Utilization and Progress Toward Eliminating Use of Highly Enriched Uranium; Nuclear and Radiation Studies Board; Division on Earth and Life Studies; National Academies of Sciences, Engineering, and Medicine.
Washington (DC): National Academies Press (US); 2016 Oct 28.
Copyright 2016 by the National Academy of Sciences. All rights reserved.

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