Free neutron

A free neutron is a neutron that exists outside of a nucleus. It is unstable and must undergo decay in order to reach a state of stability. A free neutron has a half-life of about ten minutes. The decay products of the free neutron are an electron, a proton, and an antineutrino. A free neutron is considered a subatomic particle.

A free neutron has an atomic number of zero and a mass number of one. Even though it does not have a proton, a free neutron is often listed as an isotope in data tables.

See Also

• Isotope
• Proton emission
• Radiation
  • Neutron radiation
• Neutron activation
• Slow neutron
• Fast neutron