Energy resolution of a photon-counting silicon strip detector
Energy resolution of a photon-counting silicon strip detector
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DOI：
10.1016/j.nima.2009.10.152
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发表时间：
2010-01-21
影响因子：
1.4
通讯作者：
Danielsson, Mats
中科院分区：
文献类型：
--
作者：
Fredenberg, Erik;Lundqvist, Mats;Danielsson, Mats
在乳房X光摄影系统中，研究了一种具有两个能量阈值的光子计数硅条探测器。初步研究已经表明了探测器的临床益处，本研究的目的是在能量分辨率方面进行优化。从以前的研究中测量、模拟或收集与能量响应相关的因素，并将其用作级联探测器模型的输入参数。对几个X射线光谱的阈值扫描被用来将阈值水平校准为能量，并验证模型。在乳房X光摄影区，探测器组件的能量分辨率被评估为在增量E/E=0.12-0.26范围内。电子噪声主导了峰值展宽，其次是相邻探测器条之间的电荷共享，以及通道到通道的阈值扩展。如果将这些影响减小到最小，则能量分辨率可以显著提高。反符合逻辑减少了电荷共享的重复计数，但擦除了所有检测到的事件的能量分辨率，并且逻辑的优化是理想的。在典型的乳房X光检查速度下，堆积被发现是次要的。(C)2009爱思唯尔B.V.保留所有权利。
A photon-counting silicon strip detector with two energy thresholds was investigated for spectral X-ray imaging in a mammography system. Preliminary studies already indicate clinical benefit of the detector, and the purpose of the present study is optimization with respect to energy resolution. Factors relevant for the energy response were measured, simulated, or gathered from previous studies, and used as input parameters to a cascaded detector model. Threshold scans over several X-ray spectra were used to calibrate threshold levels to energy, and to validate the model. The energy resolution of the detector assembly was assessed to range over Delta E/E=0.12-0.26 in the mammography region. Electronic noise dominated the peak broadening, followed by charge sharing between adjacent detector strips, and a channel-to-channel threshold spread. The energy resolution may be improved substantially if these effects are reduced to a minimum. Anti-coincidence logic mitigated double counting from charge sharing, but erased the energy resolution of all detected events, and optimization of the logic is desirable. Pile-up was found to be of minor importance at typical mammography rates. (C) 2009 Elsevier B.V. All rights reserved.