Must not be confused with fissile Isotope.

A fissile isotope is likely to fission under the effect of fast neutron bombardment. All the heavier atoms are fissile, while very few of them are fissile.

From a fissile isotope, energy can be experimentally extracted in a fast neutron reactor, but it can not by itself undergo a chain reaction, unlike fissile isotopes, which only require a little excitement to have fun.

Fissile isotopes do not pose a threat of nuclear proliferation, unlike fissile isotopes, which must be controlled internationally.

Exemples :

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