Real Time Extremity Dosimetry

实时肢体剂量测定

• 批准号: ST/K00025X/1
• 负责人: John Lees
• 金额: $ 11.19万
• 依托单位: University of Leicester
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2012
• 资助国家: 英国
• 起止时间: 2012 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=ST%2FK00025X%2F1
• 关键词: Real; Time; Extremity; Dosimetry

Current extremity dosimetry can be divided into two classes (a) integrating material ("film" badges etc.) and (b) event counting or electronic monitoring which uses semiconductor sensors to measure the ionising radiation (eg. Figure 1 ). The former are now predominately themoluminescence dosimeters (TLD) which contain a thin layer of sensitive lithium fluoride powder. Thermoluminescent materials store the energy absorbed from ionising radiation until they are heated (in this case to about 250C), when the energy is released as light. The amount of light released is proportional to the radiation dose. After a prescribed period of use by the monitored person (weeks to months) the dosimeters are sent for processing. The major disadvantage of this type of system is that sudden high doses are not detected until after the event and cannot necessarily be correlated with a particular incident. Electronic dosimeters can overcome this major limitation, but the existing commercially available systems have their own problems, some of which are: (a) the size of the sensors (>30 mm long) means that they cannot be worn comfortably on the extremities (e.g. fingers) and interfere with the dexterity of the worker increasing the exposed dose, (b) they suffer from mechanic vibration giving false instantaneous dose rates and (c) they have a non-linear response dependent on dose rate.The market appears ready for a new type of sensor which can overcome these major issues and offer improved performance.Our business idea is to develop compound semiconductor sensors to improve the quality of extremity dose monitoring.

目前的肢体剂量测定可分为两类：（a）整合材料（“薄膜”徽章等）以及（B）事件计数或电子监控，其使用半导体传感器来测量电离辐射（例如，图1）。前者现在主要是热致发光剂量计，它含有一层薄薄的敏感氟化锂粉末。热致发光材料储存从电离辐射吸收的能量，直到它们被加热（在这种情况下，加热到约250 ℃），当能量以光的形式释放时。释放的光量与辐射剂量成正比。在受监测人员使用规定时间（数周至数月）后，将剂量计送去处理。这类系统的主要缺点是，直到事件发生之后才检测到突然的高剂量，而且不一定与特定事件相关。电子剂量计可以克服这一主要限制，但现有的商用系统有其自身的问题，其中一些是：（a）传感器的尺寸（>30 mm长）意味着它们不能舒适地佩戴在四肢上（例如手指）并干扰工人的灵活性，从而增加暴露剂量，（B）它们遭受机械振动，给出错误的瞬时剂量率，以及（c）它们具有非线性响应依赖于剂量率。市场似乎已经准备好了一种新型的传感器，可以克服这些主要问题，并提供更好的性能。我们的经营理念研制化合物半导体传感器，提高肢体剂量监测的质量。

项目成果

Characterization of GaAs mesa photodiodes with X-ray and ?-ray photons

用 X 射线和 γ 射线光子表征 GaAs 台面光电二极管

• DOI: 10.1016/j.nima.2014.04.028
• 发表时间: 2014
• 期刊: Accelerators, Spectrometers, Detectors and Associated Equipment
• 作者: Barnett A