Gamma ray sensitivity of neutron detector based on microchannel plate
-
摘要: 研制了一种基于微通道板的超快脉冲中子探测器，对其γ射线灵敏度进行了理论和实验研究。建立了探测器的γ射线灵敏度理论计算模型，利用蒙特卡罗方法模拟计算了不同能量γ射线在不同厚度聚乙烯靶中产生的出射电子能谱和出射角度分布，并结合经验公式计算了单个电子在微通道板(MCP)孔道中产生的二次电子产额，最后得到了探测器的γ射线灵敏度，结果表明当聚乙烯靶厚度大于某一值时，γ射线灵敏度基本相同。利用西北核技术研究所的标准γ射线放射源对探测器的γ射线灵敏度进行了实验标定，实验结果与理论计算结果一致。Abstract: A new ultrafast pulse neutron detector based on MCP is introduced. The γ-ray sensitivity of the detector was investigated through simulation and experiment. A model of theoretical simulation was set up for γ-ray sensitivity calculation. In this model, the energy spectra and emitting angle distribution of electrons which were produced by different energy's γ-ray injecting into the different thickness' polyethylene were calculated through Monte Carlo methods. Then, the yields of secondary electrons produced by the single electron injecting into microchannel of MCP were also calculated through the experiential formula. The γ-ray sensitivity of the detector was finally obtained. The results shown that the γ-ray sensitivity of the detector was almost constant when the thickness of polyethylene was above a certain value. Some experiments were performed to test the γ-ray sensitivity at the standard gamma ray sources of Northwest Institute of Nuclear Technology. The simulated results agree with the results of experiments considering the uncertainties.
-
图 1 基于微通道板的超快脉冲中子探测器结构图
Figure 1. Structure of the ultrafast pulse neutron detector based on MCP
图 2 1.25 MeV γ射线在不同厚度聚乙烯中产生的电子能谱
Figure 2. Energy spectra of electrons produced from different thickness'polyethylene by 1.25 MeV γ-ray
图 3 1.25 MeV γ射线在不同厚度聚乙烯中产生的电子出射角度分布
Figure 3. Angle distribution of electrons produced from different thickness'polyethylene by 1.25 MeV γ-ray
图 4 γ射线在不同厚度聚乙烯中产生的电子能谱
Figure 4. Energy spectra of electrons produced from different thickness'polyethylene by 0.662 MeV γ-ray
图 5 0.662 MeV γ射线在不同厚度聚乙烯中产生的电子出射角度分布
Figure 5. Angle distribution of electrons produced from different thickness'polyethylene by 0.662 MeV γ-ray
图 6 不同能量电子产生的二次电子产额
Figure 6. Yields of secondary electrons produced by different energyelctrons
图 7 单个出射电子产生的二次电子产额
Figure 7. Yields of secondary electrons produced by single emitted electron
图 8 探测器的γ射线灵敏度理论计算结果
Figure 8. Theoretical calculation results of the detector's γ-ray sensitivity
表 1 1.25 MeV γ射线灵敏度实验结果和理论计算结果
Table 1. Experimental results and theoretical calculation results of 1.25 MeV γ-ray
thickness/mm total current/nA γ-ray flux rate/(cm-2·s-1) total γ-ray sensitivity/(C·cm2) current of background/nA γ-ray sensitivity of background/(C·cm2) experimental γ-ray sensitivity/(C·cm2) theoretical γ-ray sensitivity/(C·cm2) 1.0 59.87 6.12×107 9.78×10-16 25.77 4.21×10-16 5.57×10-16 5.86×10-16 2.0 82.18 6.12×107 1.34×10-15 25.77 4.21×10-16 9.20×10-16 9.02×10-16 3.0 91.35 6.12×107 1.49×10-15 25.77 4.21×10-16 1.07×10-15 1.05×10-15 4.0 91.07 6.12×107 1.49×10-15 25.77 4.21×10-16 1.07×10-15 1.12×10-15 5.0 92.24 6.12×107 1.51×10-15 25.77 4.21×10-16 1.08×10-15 1.12×10-15 
下载: 导出CSV
表 2 0.662 MeV γ射线灵敏度实验结果和理论计算结果
Table 2. Experimental results and theoretical calculation results of 0.662 MeV γ-ray
thickness/mm total current/nA γ-ray flux rate/(cm-2·s-1) total γ-ray sensitivity/(C·cm2) current of background/nA γ-ray sensitivity of background/(C·cm2) experimental γ-ray sensitivity/(C·cm2) theoretical γ-ray sensitivity/(C·cm2) 1.0 1.95 1.33×106 1.47×10-15 0.96 7.22×10-16 7.48×10-16 7.17×10-16 2.0 2.01 1.33×106 1.51×10-15 0.96 7.22×10-16 7.88×10-16 7.67×10-16 3.0 2.05 1.33×106 1.54×10-15 0.96 7.22×10-16 8.18×10-16 7.62×10-16 4.0 2.11 1.33×106 1.59×10-15 0.96 7.22×10-16 8.67×10-16 7.64×10-16 5.0 2.14 1.33×106 1.61×10-15 0.96 7.22×10-16 8.88×10-16 7.55×10-16
下载: 导出CSV
-
[1] 傅依备, 杨建国, 江文勉, 等. 惯性约束聚变与强激光技术[C]. 绵阳: 中国工程物理研究院核物理与化学研究所, 1990: 146-151.Fu Yibei, Yang Jianguo, Jiang Wenmian, et al. Inertial confinement fusion and high power laser technology. Mianyang: Institute of Nuclear Physics and Chemistry, CAEP, 1990: 146-151 [2] 张小东. 基于反冲质子法的MCP超快脉冲中子探测器技术研究[D]. 西安: 西北核技术研究所, 2017: 11-30.Zhang Xiaodong. Technology of the ultrafast pulse neutron detector based on recoil proton and MCP. Xi'an: Northwest Institute of Nuclear Technology, 2017: 11-30 [3] 潘京生. 低噪声高分辨力微通道板研制[D]. 南京: 南京理工大学, 2008: 5-8.Pan Jingsheng. The developments of low noise high resolution microchannel plate. Nanjing: Nanjing University of Science and Technology, 2008: 5-8 [4] 胡松. 微通道板光电倍增管性能研究[D]. 南京: 南京理工大学, 2009: 7.Hu Song. Performances research of microchannel plate photomultiplier. Nanjing: Nanjing University of Scienee and Technology, 2009: 7 [5] 黄展常, 杨建伦, 李国栋. 波形比较法测量MCP-PMT对强窄脉冲的线性输出[J]. 原子能科学技术, 2016, 50(3): 553-557. https://www.cnki.com.cn/Article/CJFDTOTAL-YZJS201603027.htmHuang Zhanchang, Yang Jianlun, Li Guodong. Measurement of MCP-PMT's linear output for narrow intensive pulse based on waveform comparison method. Atomic Energy Science and Technology, 2016, 50(3): 553-557 https://www.cnki.com.cn/Article/CJFDTOTAL-YZJS201603027.htm [6] Dewald E L, Campbell K M, Turner R E, et al. Dante soft X-ray power diagnostic for National Ignition Facility[J]. Review of Scientific Instruments, 2004, 75(10): 3759-3761. [7] Glenn F. Radiation detection and measurement[M]. New York: John Wiley&Sons, Inc, 1999: 48-53. [8] 刘腊群, 刘大刚, 王学琼, 等. 三维PIC数值模拟中二次发射的实现[J]. 强激光与粒子束, 2012, 24(8): 1980-1984. doi: 10.3788/HPLPB20122408.1980Liu Laqun, Liu Dagang, Wang Xueqiong, et al. Implementation of secondary emission in three dimensional PIC numerical simulation. High Power Laser and Particle Beams, 2012, 24(8): 1980-1984 doi: 10.3788/HPLPB20122408.1980 [9] 毛世峰. 扫描电子显微学中二次电子产生的Monte Carlo模拟[D]. 合肥: 中国科学技术大学, 2009: 45.Mao Shifeng. Monte Carlo simulation study on the generation of secondary electrons in scanning electron microscopy. Hefei: University of Science and Technology of China, 2009: 45 [10] 彭玲玲. 微通道板薄膜打拿极二次电子发射特性研究[D]. 长春: 长春理工大学, 2014: 38-42.Peng Lingling. Investigation of microchannel plate film dynode and secondary electron emission characteristics. Changchun: Changchun University of Science and Technology, 2014: 38-42 [11] 吴治华, 赵国庆, 陆福全, 等. 原子核物理实验方法[M]. 北京: 原子能出版社, 1994: 472-474.Wu Zhihua, Zhao Guoqing, Lu Fuquan, et al. Experimental methods of nuclear physics. Beijing: Atomic Energy Press, 1994: 472-474 [12] 张小东. 基于气体闪烁体的裂变中子总数测量技术研究[D]. 西安: 西北核技术研究所, 2010: 17-18.Zhang Xiaodong. Technology of measuring total number of fission neutron based on gas scintillator. Xi'an: Northwest Institute of Nuclear Technology, 2010: 17-18 -
点击查看大图
计量
- 文章访问数: 1156
- HTML全文浏览量: 286
- PDF下载量: 247
- 被引次数: 0
