Digital X-ray imaging systems for megaelectronvolt (MeV)-range photon beams are based on a combination of a scintillator screen and either a camera or an amorphous silicon array. To limit dose rate on electronics and enhance imaging device lifetime, the scintillator screen can be mirror-coupled to the camera. Performances of such devices are a compromise between exposure time and spatial resolution. These technical characteristics are especially scintillator-dependent. In this article, we present, in the first part, a performance evaluation of six different scintillators with a 9-MeV Bremsstrahlung X-ray source. The tested scintillators are composed of one microstructured CsI:Tl scintillator, two phosphor [Gd2O2S (GOS)] screens, and three transparent scintillators. These scintillators present a wide range of density, thickness, and conversion efficiency. The scintillator’s performance assessment is based on the combination of light output and spatial resolution. The results are helpful to guide design and engineering of high-energy imaging devices adapted to specific requirements. In the second part, imaging performance comparison is done between our current GOS screen detector and a new CsI screen detector.

中文翻译：

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用于严重事故实验的快速 MeV X 射线成像的探测器升级

用于兆电子伏 (MeV) 范围光子束的数字 X 射线成像系统基于闪烁体屏幕和相机或非晶硅阵列的组合。为了限制电子设备的剂量率并提高成像设备的使用寿命，闪烁体屏幕可以镜面耦合到相机。这种设备的性能是曝光时间和空间分辨率之间的折衷。这些技术特性尤其依赖于闪烁体。在本文中，我们在第一部分介绍了对具有 9-MeV 轫致辐射 X 射线源的六种不同闪烁体的性能评估。测试的闪烁体由一个微结构 CsI:Tl 闪烁体、两个磷光体 [Gd2O2S (GOS)] 屏幕和三个透明闪烁体组成。这些闪烁体具有广泛的密度、厚度、和转换效率。闪烁体的性能评估基于光输出和空间分辨率的组合。结果有助于指导适应特定要求的高能成像设备的设计和工程。在第二部分中，我们在当前的 GOS 屏幕探测器和新的 CsI 屏幕探测器之间进行了成像性能比较。