A high sensitivity 4π view gamma imager with a monolithic 3D position-sensitive detector
A high sensitivity 4π view gamma imager with a monolithic 3D position-sensitive detector
复制标题
具有单片 3D 位置敏感探测器的高灵敏度 4 pi 视图伽玛成像仪
DOI：
10.1016/j.nima.2019.05.022
复制
发表时间：
2019-09-01
影响因子：
1.4
通讯作者：
Ma, Tianyu
中科院分区：
文献类型：
--
作者：
Ye, Qing;Fan, Peng;Ma, Tianyu
在核安全、公共卫生和国土安全应用中，成像是调查伽马辐射热点的有效方法。现有的伽马成像器或者配备限制成像视场（FOV）和灵敏度的准直器，或者在没有准直器的情况下工作，但是需要具有复杂的数据处理和图像重建方法的高性能检测器，例如康普顿相机。在这项工作中，我们证明了一个高灵敏度的4 π视图伽玛成像仪的设计概念的可行性。基于单片3D位置敏感探测器内部的光子事件密度分布，成像器重建探测器所暴露的周围伽马热点的4 pi视图。蒙特卡罗模拟和实验进行了几种配置的周围稀疏伽玛点源的能量范围从0.1到1.5 MeV。结果表明，重建的4 pi视图图像可以识别多个伽玛热点，热点的定位精度和分辨率取决于探测器的固有分辨率和采集数据的统计特性。我们的结论是，所提出的设计可用于测量伽马热点在核安全应用。
Imaging is an effective way to survey gamma radiation hotspots in nuclear safety, public health and homeland security applications. The existing gamma imagers either equip a collimator, which limits the imaging field of view (FOV) and sensitivity, or work without a collimator but require a high performance detector with sophisticated data processing and image reconstruction methods, e.g. the Compton camera. In this work, we demonstrate the feasibility of a high sensitivity 4 pi view gamma imager design concept. Based on the photon event density distribution inside a monolithic 3D position-sensitive detector, the imager reconstructs the 4 pi view of the surrounding gamma hotspots that the detector is exposed to. Monte Carlo simulations and experiments were conducted for several configurations of surrounding sparse gamma point sources in the energy range from 0.1 to 1.5 MeV. The results show that the reconstructed 4 pi view image can identify multiple gamma hotspots, with the hotspots' positioning accuracy and resolution dependent on the detector's intrinsic resolution and the statistics of the acquired data. We conclude that the proposed design can be used for surveying gamma hotspots in nuclear security applications.