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Concept information

Preferred term

alpha particle  

Definition

  • An alpha particle is a kind of particle emitted spontaneously during the type of radioactive decay known as alpha decay. An alpha particle is identical with the nucleus of a helium atom (⁴He), consisting of two protons and two neutrons. The rest mass of the alpha particle is 6.64424 × 10⁻²⁷ kg, or 3.7273 × 10⁹eV. Alpha particles have a low penetrating power and a short range (a few cm in air). The most energetic of them (up to 7.5 MeV) will generally fail to penetrate the dead layers of cells covering the skin and can be easily stopped by a sheet of paper. Alpha particles play an important role in nuclear fusion processes within stars. (Encyclopedia of Science, by David Darling, https://www.daviddarling.info/encyclopedia/A/alphapart.html)

Broader concept

Entry terms

  • alpha radiation
  • alpha ray
  • α particle
  • α radiation
  • α ray

In other languages

  • French

  • particule α
  • rayon alpha
  • rayon α
  • rayonnement alpha
  • rayonnement α

URI

http://data.loterre.fr/ark:/67375/MDL-NP7PL9T7-2

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