用GR-200A热释光探测器测量医用高能电子线剂量

Study on application of GR-200A thermoluminescence detector in measurement of medical high energy electronic dose

目的 为掌握GR-200A热释光探测器对电子线剂量测量的最佳条件,了解该探测器在剂量测量中的实用性。方法 使用RTS-200二维扫描水箱、ELEKTA Precise医用电子直线加速器及RGD-3B热释光剂量测量仪等设备进行了相关研究。结果 通过水箱分析医用高能电子线的剂量分布特征,可精确确定GR-200A热释光探测器的剂量测量位点,适于在热释光剂量学研究和应用实践中推广;在准确定位照射下,该探测器对4～8 Mev电子线的能量响应在5％以内、剂量率标准偏差和剂量线性偏差分别为2.3％和4％,可初步实现放射治疗剂量和个人剂量当量Hp(d)的测量。结论GR-200A热释光探测器在医用高能电子线剂量测量中有一定的实用价值。

Objective To grasp the best tesang condition of electronic dose by means of GR-200A TLD(Thermoluminescence Detector) and to understand the practical use of the detector in dose measurement. Methods RTS-200 scanrung water phantom(two dimension), ELEKTA Precise medical electronic Linear accelerator, RGD-3B thermoluminescence dosimeter and so on are betaken in these studies. Results The point of dose measurement of GR-200A Detector can be located precisely through analyzing dose distributing features of the accelerator by using scanning water phantom, which should be popularized in research and practice of thermoluminescence dosimetry. Simultaneously, under the condition of being exposed correctly of the detector at the range of 4-8 MeV of electron energy, less than 5% of energy response, 2.3% standard error of dose rate and 4% of dose linearity deviation can be found. Hence, neasurement of radiotherapeutic dose and personal dose equivalent can be carried out. Conclusion The practical value of GR-200A thermoluminescence detector is embodied in measurement of medical high energy electronic dose.