关键词: 激光尾场加速/
高能X射线/
无损检测/
成像探测器
English Abstract
Detector characterization and electron effect for laser-driven high energy X-ray imaging
Zhang Tian-Kui1,Yu Ming-Hai1,
Dong Ke-Gong1,
Wu Yu-Chi1,2,
Yang Jing1,
Chen Jia1,
Lu Feng1,
Li Gang1,
Zhu Bin1,
Tan Fang1,
Wang Shao-Yi1,
Yan Yong-Hong1,
Gu Yu-Qiu1,2
1.Science and Technology on Plasma Physics Laboratory, Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900, China;
2.IFSA Collaborative Innovation Center, Shanghai Jiao Tong University, Shanghai 200240, China
Fund Project:Project supported by the National Natural Science Foundation of China (Grant Nos. 11505166, 11174259, 11375161, 11405159), the Foundation of Science and Technology on Plasma Physics Laboratory, China (Grant Nos. 9140C680301150C68297, 9140C680302130C68242), and the National Key R&D Program of China (Grant No. 2016YFA0401100).Received Date:25 June 2017
Accepted Date:17 August 2017
Published Online:05 December 2017
Abstract:High energy X-ray sources based on laser-wakefield accelerated electron beams have several important advantages, including high photon energy and small source size, and have many important applications such as high resolution radiography in non-destructive testing. Firstly, the thickness of electron converter is optimized with the targets Ta, W and Pb each with an optimal thickness of 2 mm. We calibrate the intrinsic spatial resolution of CsI needle-like scintillation screen, bismuth germanium oxide (BGO) scintillation array and DRZ scintillation screen with an X-ray tube. And the spatial resolution of CsI needle-like scintillation screen is as high as 8.7 lp/mm. The energy deposition responses of these three detectors to high X-ray are also simulated. Experiments show that the features of a two-layer object can be resolved up to an area density of 33.0 g/cm2 by using the high X-ray source generated by injecting laser-wakefield accelerated electron beam into a Ta convertor target. Experiment that compares X-ray radiography, mixed radiography of X-ray and electron, and electron radiography, is also carried out. Since low X-ray yield and low detection efficiency are two serious problems in high energy X-ray radiography based on laser-wakefield accelerated electron beams, we propose and prove a method of improving image signal intensity greatly at the cost of image contrast by adopting the mixed radiography of X-ray and electron.
Keywords: laser wakefield acceleration/
high energy X-ray/
non-destructive testing/
imaging detector
