Suitability of pure nanocrystalline LiF as a TLD dosimeters for high dose gamma radiation

Amer, H.; El Ashmawy, M.; Al Azab, H.; Ezz El-Din, M. R.

doi:10.21608/jsrs.2016.15626

Suitability of pure nanocrystalline LiF as a TLD dosimeters for high dose gamma radiation

Document Type : Original Article

Authors

Nuclear and Radiological Regulatory Authority, 3-Ahmed El-Zomor Street, El-Zohour District, Nasr City, 11762 Cairo, Egypt.

10.21608/jsrs.2016.15626

Abstract

LiF is an alkali halide that is commonly used in radiation dosimetry utilizing its well known thermoluminescence property. Pure LiF has very limited use in radiation dosimetry since the density and types of the internal traps are limited. For that reason, LiF usually are doped with different elements such as Mg and Ti in (TLD-100) to enhance its TL properties and to be suitable for dosimetry applications. In this work we used ball milling as an alternative to dopants (impurities) to induce structure defects (e.g. dislocation) that will play the major role in TL process instead to dopants. A pristine LiF was milled for 1 hour and compressed in form of chips then annealed for 1 h at 600 ^oC to get rid of low temperature dislocations. The annealed samples showed linear response in the range 50-300 Gy. Fading investigation showed that the overall integral TL intensity almost stabilizes after 12 day from first irradiation. The study indicates that ball milling is new promising technique to produce TL dosimeters free of dopants.

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