Structure design of thick pinhole with double cones for spot size measurement of the linear induction accelerator light source
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摘要: 研究设计双锥厚针孔结构体,利用小孔成像测量高能强流直线感应加速器光源的焦斑。建立数值计算模型,根据实际光源特性和实验布局条件,模拟光子穿过厚针孔结构的辐射成像过程,分析光源尺寸、分布和偏轴等对焦斑测量的影响。理论计算结果显示对光源物面的空间分辨率可达5 lp/mm。Abstract: The structure of thick pinhole with double cones is studied and designed for the spot size measurement of the high-energy intense-current linear induction accelerator (LIA) light source. The theoretical model for numerical calculations is built up according to the parameters of the light source and the practical layout of the experimental measurement. The imaging process of photons penetrating through the thick pinhole structure is simulated, and the impact of the spot size, distribution and off axis on the source spot measurement is analyzed. Calculated results show that the spatial resolution on the source plane reaches 5 lp/mm.
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Key words:
- linear induction accelerator /
- X-ray spot /
- thick pinhole
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表 1 双锥厚针孔成像的焦斑FWHM计算结果
Table 1. Results of source FWHM by thick pinhole imaging
distribution source FWHM / mm L2=1 m L2=2 m L2=3 m δFWHMcal/mm Δ δFWHMcal/mm Δ δFWHMcal/mm Δ KV 1.00 0.94 -6.5% 0.96 -3.6% 0.97 -3.1% 1.10 1.04 -5.6% 1.06 -3.2% 1.07 -2.7% 1.30 1.24 -4.4% 1.27 -2.6% 1.27 -2.3% 1.50 1.45 -3.6% 1.47 -2.2% 1.47 -2.0% GS 1.00 1.06 5.6% 1.01 0.7% 1.00 0.2% 1.10 1.15 4.2% 1.10 0.0% 1.09 -0.5% 1.30 1.33 1.9% 1.28 -1.2% 1.28 -1.7% 1.50 1.51 0.4% 1.47 -2.0% 1.46 -2.5% BNT 1.00 1.10 10.2% 1.03 2.7% 1.02 1.8% 1.10 1.19 7.8% 1.12 2.0% 1.11 0.7% 1.30 1.36 4.3% 1.30 -0.2% 1.29 -0.8% 1.50 1.53 2.0% 1.48 -1.4% 1.46 -3.0% QBNT 1.00 1.12 11.7% 1.03 3.2% 1.02 2.5% 1.10 1.20 9.2% 1.13 2.4% 1.11 1.2% 1.30 1.37 5.5% 1.30 -0.1% 1.30 -0.2% 1.50 1.54 2.8% 1.49 -1.0% 1.47 -1.9% -
[1] 邓建军, 丁伯南, 王华岑, 等. "神龙一号"直线感应加速器物理设计[J]. 强激光与粒子束, 2003, 15(5): 502-504. http://www.hplpb.com.cn/article/id/2132Deng Jianjun, Ding Bonan, Wang Huacen, et al. Physical design of the Dragon-Ⅰ linear induction accelerator. High Power Laser and Particle Beams, 2003, 15(5): 502-504 http://www.hplpb.com.cn/article/id/2132 [2] 石金水, 邓建军, 章林文, 等. 神龙二号加速器及其关键技术[J]. 强激光与粒子束, 2016, 28: 010201. doi: 10.11884/HPLPB201628.010201Shi Jinshui, Deng Jianjun, Zhang Linwen, et al. Dragon-Ⅱ accelerator and its key technology. High Power Laser and Particle Beams, 2016, 28: 010201 doi: 10.11884/HPLPB201628.010201 [3] 施将君. 高能闪光照相引论[M]. 中物院流体物理研究所科技丛书, 1998.Shi Jiangjun. Introduction of high-energy flash radiography. Scientific book series of IFP, 1998 [4] 谢红卫, 彭太平, 许泽平, 等. 应用于高能伽马射线源图像诊断的厚针孔设计[J]. 核电子学与核探测技术, 2011, 31(2): 143-147. https://www.cnki.com.cn/Article/CJFDTOTAL-HERE201102007.htmXie Hongwei, Peng Taiping, Xu Zeping, et al. Thick pinhole design applied to high energy γ-ray source radiographic diagnostics. Nuclear Electronics and Detection Technology, 2011, 31(2): 143-147 https://www.cnki.com.cn/Article/CJFDTOTAL-HERE201102007.htm [5] 谢红卫, 宋顾周, 张占宏, 等. 厚针孔成像模型计算[J]. 试验与研究, 2004, 27(2): 19-29.Xie Hongwei, Song Guzhou, Zhang Zhanhong, et al. Simulating of pinhole imaging. Test & Research, 2004, 27(2): 19-29 [6] Ekdahl C. Characterizing flash-radiography source spots[J]. Journal of the Optical Society of America A, 2011, 28(12): 2501-2509. doi: 10.1364/JOSAA.28.002501 [7] Muller K H. Measurement and characterization of X-ray spot size[R]. LA-UR-89-1886, 1989. [8] 王毅, 李勤, 代志勇. 蒙特卡罗模拟分析电子束发射度对照射量空间分布影响[J]. 强激光与粒子束, 2017, 29: 065006. doi: 10.11884/HPLPB201729.170029Wang Yi, Li Qin, Dai Zhiyong. Analysis on influence of beam emittance on spatial distribution of exposure using Monte Carlo simulation. High Power Laser and Particle Beams, 2017, 29: 065006 doi: 10.11884/HPLPB201729.170029 [9] Hubbell J H, Seltzer S M. Tables of X-ray mass attenuation coefficients and mass energy-absorption coefficients 1 keV to 20 MeV for elements Z=1 to 92 and 48 additional substances of dosimetric interest[R]. NISTIR 5632, 1995. [10] 赵凯华, 钟锡华. 光学[M]. 北京: 北京大学出版社, 2002.Zhao Kaihua, Zhong Xihua. Optics. Beijing: Peking University Press, 2002