Malthez Anna L M C, Marczewska Barbara, Ferreira Felisberto, Umisedo Nancy K, Nowak Tomasz, Bilski Pawel, Yoshimura Elisabeth M
Federal University of Technology - Parana, Av. Desembargador Westphalen, 637, Bloco N, Physics Academic Department, CEP 80010-110 Curitiba, PR, Brazil.
Institute of Nuclear Physics of Polish Academy of Sciences, Radzikowskiego 152, 31-342 Krakow, Poland.
Appl Radiat Isot. 2018 May;135:166-170. doi: 10.1016/j.apradiso.2018.01.041. Epub 2018 Jan 31.
Calcium fluoride (CaF), in both natural and synthetic forms, has been exhaustively studied and explored as thermoluminescent (TL) detector. However its sensitivity to ambient light points to the applicability of CaF as OSL (Optically Stimulated Luminescence) detector, increasing the research about its luminescent properties. Although some properties to employ CaF detectors with OSL technique have been already demonstrated, there is a lack of some essential information as the OSL response to different types and energy of ionizing radiation. In order to extend the use of Brazilian natural CaF with OSL technique, we evaluated the efficiency and dosimetric properties of cold pressed CaF:NaCl pellets. The CaF detectors presented good reproducibility and negligible fading of the signal over one month after irradiation. The dose response using OSL, TL and residual TL showed linear behavior for different radiation beams (protons, photons and alpha and beta particles), being equivalent to the results obtained with BeO and MTS (LiF) detectors through OSL and TL technique respectively. Moreover, differences were observed in OSL efficiency according the beam type and energy; CaF detectors presented a higher OSL and TL sensitivities to protons, photons and beta particles than to alpha particles. The energy response to photons obtained using OSL and residual TL intensities present an over response at lower photon energy similar to TL energy response. In addition, differences in the OSL curve shapes were observed according to radiation type and energy, pointing to the possibility of applying this material in mixed radiation fields and to estimate average LET (Linear Energy Transfer).
天然和合成形式的氟化钙（CaF）作为热释光（TL）探测器已经得到了详尽的研究和探索。然而，其对环境光的敏感性表明CaF可作为光激发发光（OSL）探测器，这增加了对其发光特性的研究。尽管已经证明了使用CaF探测器进行OSL技术的一些特性，但仍缺乏一些基本信息，例如OSL对不同类型和能量的电离辐射的响应。为了扩展巴西天然CaF在OSL技术中的应用，我们评估了冷压CaF:NaCl颗粒的效率和剂量学特性。CaF探测器具有良好的重现性，并且在辐照后一个月内信号的衰减可忽略不计。使用OSL、TL和残余TL的剂量响应对于不同的辐射束（质子、光子以及α和β粒子）呈现出线性行为，分别与通过OSL和TL技术使用BeO和MTS（LiF）探测器获得的结果相当。此外，根据束流类型和能量观察到OSL效率存在差异；CaF探测器对质子、光子和β粒子的OSL和TL灵敏度高于对α粒子的灵敏度。使用OSL和残余TL强度获得的对光子的能量响应在较低光子能量下呈现出过度响应，类似于TL能量响应。此外，根据辐射类型和能量观察到OSL曲线形状存在差异，这表明该材料有可能应用于混合辐射场并估计平均传能线密度（LET）。
