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 soon disappear. In this sense, neutron activation is a non-destructive analysis method. Neutron activation analysis can be done in situ. For example, aluminium (Al-27) can be activated by capturing relatively low-energy neutrons to produce the isotope Al-28, which decays with a half-life of 2.3 minutes with a decay energy of 4.642 MeV. This activated isotope is used in oil drilling to determine the clay content (clay is generally an alumino-silicate) of the underground area under exploration. Historians can use accidental neutron activation to authenticate atomic artifacts and materials subjected to neutron fluxes from fission incidents. For example, one of the fairly unique isotopes found in trinitite, and therefore with its absence likely signifying a fake sample of the mineral, is a barium neutron activation product, the barium in the Trinity device coming from the slow explosive lens employed in the device, known as Baratol. Semiconductor production Neutron irradiation may be used for float-zone silicon slices (wafers) to trigger fractional transmutation of Si atoms into phosphorus (P) and therefore doping it into n-type silicon See also Induced radioactivity Neutron activation analysis Phosphorus-32 produced when sulfur captures a neutron. Salted bomb Table of nuclides References External links Neutron Activation Analysis web Handbook on Nuclear Activation Cross-Sections, IAEA, 1974 Decay Data in MIRD Format from the National Nuclear Data Center at Brookhaven National Laboratory Neutron capture as it relates to nucleosynthesis Neutron capture and the Chart of the nuclides The chart of the Nuclides Discovery of the Chromium isotopes, Chromium-55 by Cr-54 neutron capture ORILL : 1D transmutation, fuel depletion, and radiological protection code Further reading Activation Radiation effects Radiation