Osl dating australia

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

"Optical dating" typically refers to OSL and IRSL, but not TL.

Recent OSL dating of stone tools in Arabia pushed the "out-of-Africa" date hypothesis of human migration back 50,000 years and added a possible path of migration from the African continent to the Arabian peninsula instead of through Europe.

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

From the conduction band they may recombine with holes trapped in hole traps.

If the centre with the hole is a luminescence center (radiative recombination centre) emission of light will occur.

The problem with this technique is that the operator does not know the individual figures that are being averaged, and so if there are partially prebleached grains in the sample it can give an exaggerated age .

In contrast to the multiple-aliquot method, the SAR method tests the burial ages of individual grains of sand which are then plotted.

Mixed deposits can be identified and taken into consideration when determining the age .

The concept of using luminescence dating in archaeological contexts was first suggested in 1953 by Farrington Daniels, Charles A. Saunders, who thought the thermoluminescence response of pottery shards could date the last incidence of heating.

The OSL dosimeter provides a new degree of sensitivity by giving an accurate reading as low as 1 mrem for x-ray and gamma ray photons with energies ranging from 5 ke V to greater than 40 Me V.

The OSL dosimeter's maximum equivalent dose measurement for x-ray and gamma ray photons is 1000 rem.

In diagnostic imaging the increased sensitivity of the OSL dosimeter makes it ideal for monitoring employees working in low-radiation environments and for pregnant workers.