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Induced Thermoluminescence. Mateo Naranjo. A brief overview of TL. What is TL? -It’s the thermally stimulated emission of light from a material What are the requirements for TL to happen?
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Induced Thermoluminescence Mateo Naranjo
A brief overview of TL • What is TL? -It’s the thermally stimulated emission of light from a material • What are the requirements for TL to happen? -The material has to be either an insulator or semiconductor (that’s why we take off all the metallic part of the meteorite first!) -Material must have been exposed to radiation -It must be stimulated by heating
So what is the difference between natural and induced TL? • Natural TL (Stacy’s part) is produced by a sample in the “as received” state. • Induced TL is produced by a sample drained off it’s NTL and subjected to a standard radiation dose. The measurement of ITL will provide info on the mineralogy and nature of the particles.
Procedures • Sample Preparation • TL (natural+induced) • Glow curve analysis • Data reduction • Final analysis & deductions
What parameters are we looking for? • For ITL, important parameter is TL sensitivity • It’s calculated as the average PH (peak height) of sample normalized to the Dhajala meteorite.
As expected, the TL sensitivity values we obtained were consistent with high type 3 / low type 4 ordinary chondrites
Can we compare these values to other parameters? • Yes! We can compare them to Olivine and Pyroxene PMD, a mineralogical measure of the scatter, and see if we spot any trends
Conclusions • Our TL sensitivity values agreed with high type 3 / low type 4 ordinary chondrites • Further comparison with PMD showed a proportionallity trend between TL sensitivity and pyroxene PMD ==> PMD goes down as TL sens. goes up • The olivine PMD shows no relation to TL sensitivity (because diffusion is much faster in ol)