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The total absorbed radiation dose is determined by exciting, with light, specific minerals (usually quartz or potassium feldspar) extracted from the sample, and measuring the amount of light emitted as a result.The photons of the emitted light must have higher energies than the excitation photons in order to avoid measurement of ordinary photoluminescence.For quartz, blue or green excitation frequencies are normally used and the near ultra-violet emission is measured.

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The trapped charge accumulates over time at a rate determined by the amount of background radiation at the location where the sample was buried.

Stimulating these mineral grains using either light (blue or green for OSL; infrared for IRSL) or heat (for TL) causes a luminescence signal to be emitted as the stored unstable electron energy is released, the intensity of which varies depending on the amount of radiation absorbed during burial and specific properties of the mineral.

It uses various methods to stimulate and measure luminescence.

It includes techniques such as optically stimulated luminescence (OSL), infrared stimulated luminescence (IRSL), and thermoluminescence dating (TL).

Luminescence dating refers to a group of methods of determining how long ago mineral grains were last exposed to sunlight or sufficient heating.

It is useful to geologists and archaeologists who want to know when such an event occurred.

This is usually, but not always, the case with aeolian deposits, such as sand dunes and loess, and some water-laid deposits.

Single Quartz OSL ages can be determined typically from 100 to 350,000 years BP, and can be reliable when suitable methods are used and proper checks are done.

Unlike carbon-14 dating, luminescence dating methods do not require a contemporary organic component of the sediment to be dated; just quartz, potassium feldspar, or certain other mineral grains that have been fully bleached during the event being dated.

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