Free neutron

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A free neutron is a neutron that exists outside of an atomic nucleus. While neutrons can be stable when bound inside nuclei, free neutrons are unstable and decay with a half-life of about ten minutes. The only possible decay mode is into a proton, an electron, and an electron antineutrino:

Related Topics:
Neutron - Atomic nucleus - Decay - Half-life - Proton - Electron - Electron antineutrino

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:hbox{n} ohbox{p}+hbox{e}^-+overline{ u}_{mathrm{e}}

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Even though it is not a chemical element, the free neutron is often included in tables of isotopes. It is then considered to have an atomic number of zero and a mass number of one.

Related Topics:
Chemical element - Atomic number - Mass number

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Nuclear reactors are designed to produce free neutrons in copious amounts; their role is to sustain the energy-producing chain reaction. The intense neutron radiation is also used to produce various radioisotopes through the process of neutron activation.

Related Topics:
Nuclear reactor - Chain reaction - Neutron radiation - Neutron activation

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