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Particle radiation is the radiation of energy by means of fast-moving subatomic particles. Particle radiation is referred to as a particle beam if the particles are all moving in the same direction, similar to a light beam. Due to the wave-particle duality, all moving particles also have wave character. Higher energy particles more easily exhibit particle characteristics, while lower energy particles more easily exhibit wave characteristics. == Types and production == Particles can be electrically charged or uncharged: Particle radiation can be emitted by an unstable atomic nucleus (via radioactive decay), or it can be the product from some other kind of nuclear reaction. Many types of particles may be emitted: * protons and other hydrogen nuclei stripped of their electrons * positively charged alpha particles (α) * helium ions at high energy levels * HZE ions, which are nuclei heavier than helium * positively or negatively charged beta particles (β+ or β−)(the latter being more common) * High speed electrons that are not from the beta decay process, but others such as internal conversion and Auger effect. * photons (called a gamma ray, γ, and acting in some ways like a particle.) * neutrons, subatomic particles which have no charge * neutrinos * mesons * muons Mechanisms that produce particle radiation include: *Auger effect *internal conversion *beta decay *cluster decay *proton emission *neutron emission *supernova explosions *solar particle events *solar flares *alpha decay *nuclear fission and spontaneous fission *nuclear fusion *particle colliders in which streams of high energy particles are smashed *Additionally, galactic cosmic rays include these particles, but many are from unknown mechanisms Charged particles (electrons, mesons, protons, alpha particles, heavier HZE ions, etc.) can be produced by particle accelerators. Ion irradiation is widely used in the semiconductor industry to introduce dopants into materials, a method known as ion implantation. Particle accelerators can also produce neutrino beams. Neutron beams are mostly produced by nuclear reactors. For the production of electromagnetic radiation, there are many methods, depending upon the wave length (see electromagnetic spectrum). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「particle radiation」の詳細全文を読む スポンサード リンク
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