title: Thermoluminescence properties of LiF:Mg,Cu,Na,Si pellets in radiation dosimetry.
abstract: Sintered LiF:Mg,Cu,Na,Si thermoluminescence (TL) pellets have been developed for application in radiation dosimetry. LiF:M,Cu,Na,Si TL pellets were made from TL powders using a sintering process, that is, pressing and heat treatment. These pellets have a diameter of 4.5 mm, and a thickness of 0.8 mm are blue in colour and have a mass of 28 mg each. After 400 pellets had been produced they were irradiated with 137Cs gamma radiation and samples having a sensitivity within a +/-5% standard deviation were selected for experimental use. In the present study, the physical and dosimetric properties of LiF:Mg,Cu,Na,Si TL pellets were investigated for their emission spectrum, dose response, energy response and fading characteristics. Photon irradiation for the experiments was carried out using X ray beams and a 137Cs gamma source at the Korea Atomic Energy Research Institute (KAERI). The average energies and the dose were in the range of 20-662 keV and 10(-6) - 10(2) Gy respectively. The glow curves were measured with a manual type thermoluminescence dosimetry reader (system 310, Teledyne) at a constant nitrogen flux and a linear heating rate. For a constant heating rate of 5 degrees C.s(-1). the main dosimetric peak of the glow curve appeared at 234 degrees C, its activation energy was 2.34 eV and the frequency factor was 1.00 x 10(23). The TL emission spectrum appeared at the blue region centred at 410 nm. A linearity of photon dose response was maintained up to 100 Gy. The photon energy responses relative to the 137Cs response were within +/-20% in the overall photon energy region. No fading of the TL sensitivity of the pellets stored at room temperature was found over the course of a year. Therefore LiF:Mg,Cu,Na,Si TL pellets can be used for personal dosimetry, but more research is needed to improve the characteristics for repeated use.
authors.affiliation: ymnam@kaeri.re.kr
authors.forename: Y M
authors.initials: YM
authors.lastname: Nam
authors.forename: J L
authors.initials: JL
authors.lastname: Kim
mesh_terms: D003300:Copper / Q000737:chemistry; D005459:Fluorides / Q000737:chemistry / Q000528:radiation effects*; D005720:Gamma Rays; D006358:Hot Temperature; D006801:Humans; D018020:Lithium Compounds / Q000737:chemistry / Q000528:radiation effects*; D008163:Luminescent Measurements; D008274:Magnesium / Q000737:chemistry; D011854:Radiochemistry; D012680:Sensitivity and Specificity; D012825:Silicon / Q000737:chemistry; D012964:Sodium / Q000737:chemistry; D013053:Spectrophotometry; D013819:Thermoluminescent Dosimetry / Q000379:methods* / Q000706:statistics & numerical data; D014965:X-Rays
chemical_list: D018020:Lithium Compounds; C027651:lithium fluoride; D003300:Copper; D012964:Sodium; D008274:Magnesium; D005459:Fluorides; D012825:Silicon