Alpha particles are emitted by radioactive nuclei such as uranium or radium in a process known as alpha decay. This sometimes leaves the nucleus in an excited state, with the emission of a gamma ray removing the excess energy.
Alpha rays are easily absorbed by materials and can travel only a few centimeters in air. They are absorbed even by tissue paper and are not generally dangerous to life unless the sources is eaten as they cannot penetrate unbroken skin. However, if Alpha radiation does enter the body they are the most dangerous, as they are the most strongly ionising, and with large enough doses can cause any or all of the symptoms of [radiation poisoning]?.
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Since Alpha radiation is known to be a couple of protons and neutrons, why should this entry be under Alpha Rays? Surely it should be a redirect to Alpha Particles? -- Dave McKee