Neutron activation 1767692 223942750 2008-07-06T16:59:10Z CosineKitty 1750493 'radioactive activation product' sounded redundantly redundant {{Cleanup|date=January 2008}} '''Neutron activation''' is the process in which [[neutron radiation]] induces [[radioactivity]] in materials, and occurs when [[Atomic nucleus|atomic nuclei]] capture [[free neutron]]s, becoming heavier and entering [[excited state]]s. The excited nucleus often decays immediately by emitting particles such as neutrons, [[proton]]s, or [[alpha particle]]s. The [[neutron capture]], even after any immediate decay, often results in the formation an unstable [[activation product]]. Such radioactive nuclei can exhibit [[half-life|half-lives]] ranging from fractions of a second to many years. In places with high [[neutron flux]]es, such as [[nuclear reactor]] cores, neutron activation contributes to material erosion, and the materials themselves must be disposed of as low-level [[radioactive waste]]. Some materials are more subject to neutron activation than others, so a suitably chosen low-activation material can significantly reduce these problems. One way to demonstrate that [[nuclear fusion]] is occurring inside a [[Farnsworth-Hirsch fusor]] is to use a [[Geiger counter]] to measure the radioactivity induced in a sheet of [[aluminum foil]]. The lasting radiation from a [[nuclear weapon]] is in large part due to the neutron activation of the bomb itself and the surrounding material. Neutron activation also has a practical use. [[Neutron activation analysis]] is one of the most sensitive and accurate methods of ''trace element analysis''. It requires no sample preparation or solubilization and can therefore be applied to objects that need to be kept intact such as a valuable piece of art. Although the activation induces radioactivity in the object, its level is typically low and its lifetime may be short, so that its effects have soon disappeared. In this sense, neutron activation is a non-destructive analysis method. ==External links== * [http://www-nds.iaea.org/reports-new/tecdocs/technical-reports-series-156.pdf Handbook on Nuclear Activation Cross-Sections, IAEA, 1974] [[Category:Radiation]] [[Category:Neutron|Radiation]] [[Category:Radiation effects]] {{nuclear-stub}} [[de:Neutronenaktivierung]] [[nl:Neutronenactivering]]