alpha particle
Noun. positively charged nucleus of a helium-4 atom (consisting of two protons and two neutrons), emitted as a consequence of radioactivity; α-particle.This is an unmodified, but possibly outdated, definition from Wiktionary and used here under the Creative Commons license. Wiktionary is a great resource. If you like it too, please donate to Wikimedia.
This entry was last updated on RefTopia from its source on 3/20/2012.