Song Y, Zhang M, Duan B J, Yan W P, Sheng L, Song G Z, Ma J M, Han C C, Yao Z M
State Key Laboratory of Intense Pulsed Radiation Simulation and Effect, Northwest Institute of Nuclear Technology, Xi'an, China.
Rev Sci Instrum. 2022 Mar 1;93(3):033702. doi: 10.1063/5.0066686.
A high-speed radiation imaging system based on an image converter of liquid scintillator filled capillary arrays has been developed, which is sensitive to x rays, gamma rays, and neutrons. This imaging system has advantages of both high spatial resolution and high sensitivity because increasing the thickness of the image converter only leads to little deterioration on imaging resolution. The capillary arrays have dimensions of 150 mm diameter and 50 mm thickness, with 100 µm diameter of each capillary. The fluorescence decay time of the filled liquid scintillator based on the mixture of p-xylene and 2,5-diphenyloxazole has been evaluated to be ∼3 ns with the single photon method under the gamma ray excitation. The spatial resolution has been experimentally evaluated to be about 1.15 and 0.6 mm, under excitation of x rays and neutrons, respectively. The imaging system has been applied for diagnosing the dynamic x-ray spot generated by the rod pinch. Two frames in single shot with 15 ns temporal resolution and 20 ns inter-frame separation time have been obtained, which show the spatiotemporal distribution of the electrons bombarding the tungsten rod, indicating the ability of this imaging system in diagnosing dynamic radiation objects. In addition, the technique of capillary arrays provides a promising path for applications of advanced liquid scintillators in the field of radiation imaging.
基于填充液体闪烁体的毛细管阵列图像转换器的高速辐射成像系统已被开发出来,该系统对X射线、γ射线和中子敏感。这种成像系统具有高空间分辨率和高灵敏度的优点,因为增加图像转换器的厚度只会导致成像分辨率的微小下降。毛细管阵列的尺寸为直径150毫米、厚度50毫米,每根毛细管的直径为100微米。在γ射线激发下,采用单光子法评估了基于对二甲苯和2,5-二苯基恶唑混合物的填充液体闪烁体的荧光衰减时间约为3纳秒。在X射线和中子激发下,实验测得的空间分辨率分别约为1.15毫米和0.6毫米。该成像系统已被应用于诊断棒箍缩产生的动态X射线光斑。获得了具有15纳秒时间分辨率和20纳秒帧间间隔时间的单次拍摄两帧图像,展示了轰击钨棒的电子的时空分布,表明该成像系统在诊断动态辐射物体方面的能力。此外,毛细管阵列技术为先进液体闪烁体在辐射成像领域的应用提供了一条有前景的途径。