Development of electron-tracking Compton imaging system with 30-um SOI pixel sensor
Development of electron-tracking Compton imaging system with 30-um SOI pixel sensor
复制标题
开发具有 30 微米 SOI 像素传感器的电子跟踪康普顿成像系统
DOI：
10.1088/1748-0221/12/01/c01045
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发表时间：
2017
影响因子：
1.3
通讯作者：
Y. Arai
中科院分区：
文献类型：
--
作者：
Y. Yoshihara;K. Shimazoe;Y. Mizumachi;H. Takahashi;K. Kamada;A. Takeda;T. G. Tsuru;Y. Arai
康普顿成像是一种不使用机械准直器定位伽马源的有用方法。在常规康普顿成像中，通过分析每个伽马射线的相互作用序列以及随后的康普顿运动学，针对每个事件在圆锥中估计伽马射线的入射方向。由于反冲电子的喷射方向的信息丢失，产生了许多锥形痕迹的形状的伪影，这降低了信噪比（SNR）和角分辨率。我们已经开发出一种先进的康普顿成像系统的能力，通过使用的组合模式的绝缘体上硅（SOI）像素探测器和GAGG探测器的反冲电子跟踪。该系统覆盖了660-1330 keV的能量范围，用于日本福岛第一核电站内污染核素（如137 Cs和134 Cs）的定位。在微像素化SOI探测器上检测由康普顿散射引起的反冲电子的喷射方向，其理论上可以用于确定每个事件的线中的伽马射线的入射方向，并且可以减少伪影的出现。我们获得了二维重建图像从第一次迭代的建议系统的137 Cs，和信噪比和角分辨率提高了与传统的康普顿成像系统。
Compton imaging is a useful method to localize gamma sources without using mechanical collimators. In conventional Compton imaging, the incident directions of gamma rays are estimated in a cone for each event by analyzing the sequence of interactions of each gamma ray followed by Compton kinematics. Since the information of the ejection directions of the recoil electrons is lost, many artifacts in the shape of cone traces are generated, which reduces signal-to-noise ratio (SNR) and angular resolution. We have developed an advanced Compton imaging system with the capability of tracking recoil electrons by using a combination of a trigger-mode silicon-on-insulator (SOI) pixel detector and a GAGG detector. This system covers the 660–1330 keV energy range for localization of contamination nuclides such as 137 Cs and 134 Cs inside the Fukushima Daiichi Nuclear Power Plant in Japan. The ejection directions of recoil electrons caused by Compton scattering are detected on the micro-pixelated SOI detector, which can theoretically be used to determine the incident directions of the gamma rays in a line for each event and can reduce the appearance of artifacts. We obtained 2-D reconstructed images from the first iteration of the proposed system for 137 Cs, and the SNR and angular resolution were enhanced compared with those of conventional Compton imaging systems.