10-50kV X射线水吸收剂量的测量与研究

Study and measurement of the water absorbed dose in 10-50 kV X-ray

X射线水吸收剂量是辐射剂量学的重要物理量,它的精确测量在放射治疗中至关重要。开展低能X射线水吸收剂量的研究与测量,可为完善水吸收剂量溯源体系及扩宽计量部门校准范围提供重要技术支持。确定低能X射线水吸收剂量的测量方法,在辐射场中使用PTW23344电离室对10-50 k V的治疗水平辐射质下的X射线水吸收剂量进行了测量。最终得到了电离室的水吸收剂量刻度因子N_D以及厚度为6 cm有机玻璃前表面的水吸收剂量D_W。本项工作为建立国内X射线水吸收剂量标准及进行国际比对提供了条件和基础。

Background： The water absorbed dose in X-ray is an important physical quantity of radiation dosimetry, whose accurate measurement is important in radiation therapy. Purpose： The research and measurement of water absorbed dose in low-energy X-ray can provide great technical support for improving the traceability system of water absorption dose and widening the calibration range of measurement department. Methods： The water absorbed dose in 10-50 kV X-ray was measured using PTW23344 ionization chamber in radiation field. Results： Finally, the water absorbed dose scale factor of the PTW23344 ionization chamber and water absorbed dose at the front surface of the 6-cm organic glass were obtained. Conclusion： This work provides the foundation for establishment of domestic X-ray water absorbed dose standard and its international comparison.