Dosimetric characteristics of LiF:Mg,Cu,Si thermoluminescent materials

Abstract

Dosimetric characteristics of LiF:Mg,Cu,Si thermoluminescent (TL) material developed at KAERI have been investigated and compared with those of commercially available LiF:Mg,Cu,P (GR-200A). LiF:Mg,Cu,Si thermoluminescence dosimeter (TLD) can be heated up to 573K without any loss of TL sensitivity or any change in the glow curve structure. High-temperature glow peak in LiF:Mg,Cu,Si is significantly lower than that in GR-200A, consequently the residual signal is only 0.025%, which is about 35 times less than that of GR-200A. The TL sensitivity of the LiF:Mg,Cu,Si TLD is about 55 and 1.1 times higher than those of the LiF:Mg,Ti (TLD-100) and GR-200A, respectively.

Influence of sintering temperatures on LiF:Mg,Cu,P with various magnesium concentrations

“…The higher Mg concentration is, the higher the sintering temperature of the maximum TL sensitivity is. Lee et al (2006) reported the TL sensitivity of the LiF:Mg,Cu,Si TLD is about 55 and 1.1 times higher than those of the LiF:Mg,Ti (TLD-100) and GR-200A, respectively. The TL sensitivity of the standard LiF:Mg,Cu,P (GR-200A) TLD is about 65 times higher than that of TLD-100 (Tang et al, 1999;Shen et al, (Tang et al, 2007(Tang et al, , 2013 and the results of the present investigation to conclude the TL sensitivity of LiF:Mg,Cu,P with 0.6 mol% of Mg at the sintering temperatures of 750 C is much higher than those of HMCP (Tang et al, 2007) and LiF:Mg,Cu,Si (Tang et al, 2013).…”

“…LiF:Mg,Cu,P with 0.6 mol% of Mg can be heated at 260 C, the residual signals can reduced greatly. An extremely low residual signal of 0.07% in LiF:Mg,Cu,P was achieved due to a lower intensity of high temperature peaks and higher maximum readout temperature of 260 C. Lee et al (2006) reported that an extremely low residual signal of 0.025% in LiF:Mg,Cu,Si was achieved due to a lower intensity of high temperature peak (peak 5) and higher maximum readout temperature of 300 C. But the TL intensity in LiF:Mg,Cu,Si developed in Korea decreased considerably when the maximum readout temperature above 260 C. In order to re-use, the samples were subjected to 260 C for 10 min annealing to recover the TL intensity and glow curve structure. This is against the aim to reduce the residual signal, which is that the TL readout in the TLD reader should be able to reset the dosimeters such that no additional oven annealing is needed for the reuse of the dosimeters.…”

“…2002). It was reported from the same institute (the third side) that relative TL sensitivity of this formulation in LiF:Mg,Cu,Si developed in Korea is 65 times higher compared to TLD-100 (Kne zevi c et al, 2011) and the relative TL sensitivity of LiF:Mg,Cu,P (GR-200A) is 100 times higher than that of TLD-100(Miljani c et al, 2002) Lee et al (2006). reported that GR-200A samples used for comparison were procured from Conqueror Electronics Technology Co. in 2005.…”

“…This new TL material also can be heated to higher temperatures. Both TLD of LiF:Mg,Cu,Si and HMCP can be heated above 240 C (Lee et al, 2006;Tang et al, 2007Tang et al, , 2012. The shape of the HMCP glow curve shows minimal differences for annealing in the range from 250 to 270 C and the TL readout value remained stable (Tang et al, 2007).…”

Influence of dopants on the glow curve structure and energy dependence of LiF:Mg,Cu,Si detectors

“…The concentration of various dopants varied over the following ranges: Mg (0-0.50 mol%), Cu (0-0.03 mol%) and Si (0-1.2 mol%). The optimum concentrations of dopants according to KAERI are as follows: Mg 0.45 mol%, Cu 0.025 mol% and Si 0.9 mol% (Lee et al, 2006). For comparison commercially available standard LiF:Mg,Ti (TLD-100) detectors made by Thermo Fisher Scientific (earlier Harshaw) were used.…”