Definition of luminescence dating
In thermoluminescence dating, this can be used to date buried objects that have been heated in the past, since the ionizing dose received from radioactive elements in the soil or from cosmic rays is proportional to age.This phenomenon has been applied in the thermoluminescent dosimeter, a device to measure the radiation dose received by a chip of suitable material that is carried by a person or placed with an object.Emission of LIGHT when ELECTRONS return to the electronic ground state from an excited state and lose the energy as PHOTONS.It is sometimes called cool light in contrast to INCANDESCENCE.High energy radiation creates electronic excited states in crystalline materials.In some materials, these states are trapped, or arrested, for extended periods of time by localized defects, or imperfections, in the lattice interrupting the normal intermolecular or inter-atomic interactions in the crystal lattice.
Many different laboratory protocols have been developed as our understanding of the fundamental behaviour of luminescence signals from quartz and feldspar has improved.
In the last 30 years, from 1967 to 1997, the use of luminescence signals from naturally occurring minerals has gone though a major metamorphosis, from thermoluminescence (TL) dating of pottery to optically stimulated luminescence (OSL) dating of sediments.
Laboratory procedures for dating sediments have been adapted from those for pottery and new procedures have been developed as the need arises.
This distinguishes luminescence from incandescence, which is light emitted by a substance as a result of heating.
Historically, radioactivity was thought of as a form of "radio-luminescence", although it is today considered to be separate since it involves more than electromagnetic radiation.