alpha decay

noun

Meaning

A type of radioactive decay in which an atomic nucleus emits an alpha particle, consisting of two protons and two neutrons, thereby decreasing its atomic number by two and its mass number by four.

Examples

  • Uranium-238 undergoes alpha decay to transform into thorium-234.
  • The heat generated inside the Earth is partly due to the alpha decay of radioactive isotopes in the mantle.

Synonyms: alpha emission, radioactive decay, alpha disintegration, nuclear transmutation