IPERION HSIntegrating Platforms for the European Research Infrastructure ON Heritage Science
Technique: Optically Stimulated Luminescence (OSL)

OSL equipment for archaeology

Devices: Risø TL-DA-20 reader, 90Sr beta irradiation source, 241Am alpha irradiation source. The two most important application fields of luminescence dating are the determination of the age of ceramic objects or fired inorganic materials on the one hand and the dating of sediments on the other. The method uses the phenomenon that during heating or exposure to light, the signal that has built up in the material of an artefact or a sediment as a result of the ionizing radiation is effectively reset and then re-accumulated. From the intensity of the light emitted it is possible to estimate the radiation dose to which the material was exposed. The annual dose-rate in the sample itself and its surrounding can be determined by various methods and then the ratio between the accumulated dose and the annual dose yields an age in years. The most common types of stimulation for luminescence dating is heating up to 500 °C (thermoluminescence, TL) or by irradiation with light of a selected wave range (optically stimulated luminescence, OSL) that is especially used for sediment dating.

Potential Results

Thermoluminescence dating relates to the last heating to ca. 500 °C, with ceramics usually the date of production. OSL dating relates to the last exposure to sunlight, with sediments the covering of the surface, e.g. by colluvium.