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thorium series
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A scientific chart illustrating the thorium radioactive decay series, with isotopes plotted by neutron number and mass number, showing their decay paths and half-lives, and including chemical symbols and atomic numbers along the top. The four radioactive series of chemical elements: (from top) the uranium series, the neptunium series, the thorium series, and the actinium series.
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A scientific chart illustrating the thorium radioactive decay series, with isotopes plotted by neutron number and mass number, showing their decay paths and half-lives, and including chemical symbols and atomic numbers along the top.
thorium series The thorium series.

thorium series

physics
Also known as: 4n series
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History

thorium series, set of unstable heavy nuclei comprising one of the four radioactive series.

This article was most recently revised and updated by Erik Gregersen.