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Would you also like to submit a review for this item? You already recently rated this item. Your rating has been recorded. Write a review Rate this item: Preview this item Preview this item. M J Aitken Publisher: Home This edition , English, Book, Illustrated edition: Physical Description xi, p. Published London ; Orlando: Martin Jim Edition U. Series Studies in archaeological science Subjects Archaeological dating.
Antiquities Thermoluminescence dating Notes Includes index. View online Borrow Buy Freely available Show 0 more links Set up My libraries How do I set up "My libraries"? These 14 locations in All: Australian National University Library. Open to the public. La Trobe University Library.
Thermoluminescence dating - Martin Jim Aitken - Google Книги
Borchardt Library, Melbourne Bundoora Campus. Open to the public ; Open to the public ; CC Open to the public N Depending on the depth of the traps the energy required to free an electron from them the storage time of trapped electrons will vary as some traps are sufficiently deep to store charge for hundreds of thousands of years. Another important technique in testing samples from a historic or archaeological site is a process known as Thermoluminescence testing. Which involves a principle that all objects absorb radiation from the environment.
This process frees electrons within elements or minerals that remain caught within the item. Thermoluminescence testing involves heating a sample until it releases a type of light. This light is then measured to determine the last time the item was heated. When irradiated crystalline material is again heated or exposed to strong light, the trapped electrons are given sufficient energy to escape.
In the process of recombining with a lattice ion, they lose energy and emit photons light quanta , detectable in the laboratory. The amount of light produced is proportional to the number of trapped electrons that have been freed which is in turn proportional to the radiation dose accumulated.
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- Thermoluminescence dating.
- Thermoluminescence dating - Wikipedia!
In order to relate the signal the thermoluminescence—light produced when the material is heated to the radiation dose that caused it, it is necessary to calibrate the material with known doses of radiation since the density of traps is highly variable. Thermoluminescence dating presupposes a "zeroing" event in the history of the material, either heating in the case of pottery or lava or exposure to sunlight in the case of sediments , that removes the pre-existing trapped electrons.
Therefore, at that point the thermoluminescence signal is zero.
As time goes on, the ionizing radiation field around the material causes the trapped electrons to accumulate Figure 2. In the laboratory, the accumulated radiation dose can be measured, but this by itself is insufficient to determine the time since the zeroing event. The Radiation Dose Rate - the dose accumulated per year-must be determined first. This is commonly done by measurement of the alpha radioactivity the uranium and thorium content and the potassium content K is a beta and gamma emitter of the sample material.
Often the gamma radiation field at the position of the sample material is measured, or it may be calculated from the alpha radioactivity and potassium content of the sample environment, and the cosmic ray dose is added in. Once all components of the radiation field are determined, the accumulated dose from the thermoluminescence measurements is divided by the dose accumulating each year, to obtain the years since the zeroing event.
Thermoluminescence dating is used for material where radiocarbon dating is not available, like sediments. Its use is now common in the authentication of old ceramic wares, for which it gives the approximate date of the last firing.