Faria L O, Lo D, Kui H W, Khaidukov N M, Nogueira M S
Centro de Desenvolvimento da Tecnologia Nuclear, Rua Mário Werneck s/n, C.P. 941, 30123-970, Belo Horizonte, MG, Brazil.
Radiat Prot Dosimetry. 2004;112(3):435-8. doi: 10.1093/rpd/nch406. Epub 2004 Oct 5.
This investigation has been performed to test the feasibility of using K2YF5:Tb3+ crystals as thermoluminescence dosemeters (TLD). K2YF5 single crystals doped with 0.2, 10.0 and 50.0 at.% of trivalent optically active Tb3+ ions as well as K2TbF5 and undoped K2YF5 crystals have been synthesized under hydrothermal conditions. Polished crystal platelets with thickness of about 1 mm have been irradiated with X and gamma rays in order to study thermoluminescent (TL) sensitivity as well as dose and energy response in terms of the Tb3+ concentration in K2YF5. Within this concentration series, K2YF5 crystals doped with 10.0 at.% Tb3+ have been found to have maximum TL response due to a broad asymmetric TL glow peak at 269 degrees C with good linearity of dose response and reproducibility of dose measurements. After deconvolution, the main dosimetric peak has been revealed to be composed of two individual peaks, both with linear TL response behaviour, centered at 210 and 269 degrees C. As it has been proved, the linear TL signal coefficient for K2Y0.9Tb0.1F5 is almost 10 times greater than that for commercial TLD-100 (LiF:Mg,Ti), irradiated with a 137Cs gamma radiation source at the same conditions. The reported results indicate that K2YF5 crystals doped with Tb3+ have potential as promising materials for radiation dosemeters.
本研究旨在测试使用K2YF5:Tb3+晶体作为热释光剂量计（TLD）的可行性。在水热条件下合成了掺杂0.2、10.0和50.0原子百分比三价光学活性Tb3+离子的K2YF5单晶，以及K2TbF5和未掺杂的K2YF5晶体。为了研究热释光（TL）灵敏度以及K2YF5中Tb3+浓度对剂量和能量的响应，用X射线和γ射线对厚度约为1mm的抛光晶体薄片进行了辐照。在该浓度系列中，发现掺杂10.0原子百分比Tb3+的K2YF5晶体具有最大的TL响应，这是由于在269℃处有一个宽的不对称TL发光峰，剂量响应具有良好的线性以及剂量测量的可重复性。解卷积后，主要剂量峰被揭示为由两个单独的峰组成，两者都具有线性TL响应行为，中心温度分别为210℃和269℃。事实证明，在相同条件下用137Csγ辐射源辐照时，K2Y0.9Tb0.1F5的线性TL信号系数几乎是商用TLD-100（LiF:Mg,Ti）的10倍。报道的结果表明，掺杂Tb3+的K2YF5晶体有潜力成为有前景的辐射剂量计材料。
