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Monte Carlo simulation and parameterized treatment on the effect of nuclear elastic scattering in high-energy proton radiography

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Chinese Physics C 2015年第7期39卷 97-101页

作者：许海波郑娜 Institute of Applied Physics and Computational Mathematics

A version of Geant4 has been developed to treat high-energy proton radiography. This article presents the results of calculations simulating the effects of nuclear elastic scattering for various test step wedges. Comparisons with experimental data are also presented. The traditional expressions of the transmission should be correct if the angle distribution of the scattering is Gaussian multiple Coulomb scattering. The mean free path（which depends on the collimator angle） and the radiation length are treated as empirical parameters, according to transmission as a function of thickness obtained by simulations. The results can be used in density reconstruction, which depends on the transmission expressions.

关键词： proton radiography multiple Coulomb scattering angle collimator nuclear elastic scattering Geant4

Transmission calculation by empirical numerical model and Monte Carlo simulation in high energy proton radiography of thick objects

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Chinese Physics C 2015年第10期39卷 127-130页

作者：郑娜许海波 Institute of Applied Physics and Computational Mathematics

An empirical numerical model that includes nuclear absorption, multiple Coulomb scattering and energy loss is presented for the calculation of transmission through thick objects in high energy proton radiography. In this numerical model the angular distributions are treated as Gaussians in the laboratory frame. A Monte Carlo program based on the Geant4 toolkit was developed and used for high energy proton radiography experiment simulations and verification of the empirical numerical model. The two models are used to calculate the transmission fraction of carbon and lead step-wedges in proton radiography at 24 GeV/c, and to calculate radial transmission of the French Test Object in proton radiography at 24 GeV/c with different angular cuts. It is shown that the results of the two models agree with each other, and an analysis of the slight differences is given.

关键词： proton radiography angular distributions scattering Gaussians Geant4 transmission

Imaging beamline for high energy proton radiography

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Chinese Physics C 2012年第8期36卷 792-796页

作者：魏涛杨国君龙继东王少恒何小中 Institute of Fluid Physics CAEP P.O. Box 919-106Mianyang 621900 China

proton radiography is a new tool for advanced hydrotesting. This article will discuss the basic concept of proton radiography first, especially the magnetic lens system. Then a scenario of 50 GeV imaging beamline will be described in every particular, including the matching section, Zumbro lens system and imaging system. The simulation result shows that the scenario of imaging beamline performs well, and the influence of secondary particles can be neglected.

关键词： proton radiography beamline image blur MCS collimator

Image blur in high energy proton radiography

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Chinese Physics C 2013年第6期37卷 100-105页

作者：魏涛杨国君龙继东石金水 Institute of Fluid Physics China Academy of Engineering Physics

proton radiography has provided a potential development direction for advanced hydrotesting, and its image blur is a crucial point that needs to be deeply studied. In this article, numerical simulation by using the Monte Carlo code Geant4 has been implemented to investigate the entire physics mechanism of high energy proton beam travelling through the object and beamline and arriving at the image plane. This article will mainly discuss the various factors which cause the image blur, including the chromatic aberration of the imaging beamline, the insumcient modulation of an incident particle＇s transverse displacement and angle deviation, the longitudinal length of an object, the influence of containment vessel and otherwise.

关键词： proton radiography image blur chromatic aberration scattering containment vessel

A design study of a magnifying magnetic lens for proton radiography

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Chinese Physics C 2012年第3期36卷 247-250页

作者：杨国君张卓魏涛何小中龙继东石金水张开志 Institute of Fluid Physics CAEP

Magnifying magnetic lenses can be used in high-energy proton microscopes. The -I lens suggested by Zumbro is analyzed in this paper, and a new type of magnetic lens called a lengthened lens is introduced. Theoretical analysis shows that the lengthened lens can form a magnifying lens, and at the same time the main advantages of a Zumbro lens are inherited. Using the My-BOC beam dynamics code, an example of the design is shown. The results show that the method of designing magnifying magnetic lenses is effective.

关键词： magnetic lens magnifying proton radiography My-BOC code

A lattice scenario for a proton radiography accelerator

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Chinese Physics C 2010年第11期34卷 1754-1756页

作者：魏涛杨国君何小中龙继东张卓王少恒杨振李伟峰李洪杨兴林王敏洪石金水张开志邓建军章林文 Chinese Academy of Engineering Physics

A proton radiography system is an accelerator-based *** high-energy proton radiography is an advanced hydrodynamics diagnostic tool,and it is the trend of radiography technology *** this paper,a 20 GeV accelerator complex scenario,including a 35 MeV linac,a 1 GeV booster and a 20 GeV main ring,is *** overall physics design of the proton radiography accelerator is described,including the design of each part of the accelerator and the choice of the main parameters.

关键词： proton radiography accelerator lattice

proton radiography of magnetic fields generated with an open-ended coil driven by high power laser pulses

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Matter and Radiation at Extremes 2016年第4期1卷 187-191页

作者： Guoqian Liao Yutong Li Baojun Zhu Yanfei Li Fang Li Mengchao Li Xuan Wang Zhe Zhang Shukai He Weiwu Wang Feng Lu Faqiang Zhang Lei Yang Kainan Zhou Na Xie Wei Hong Yuqiu Gu Zongqing Zhao Baohan Zhang Jie Zhang National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190China Science and Technology on Plasma Physics Laboratory Laser Fusion Research CenterChina Academy of Engineering Physics(CAEP)Mianyang 621900China Key Laboratory for Laser Plasmas(MoE)and Department of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA(CICIFSA) Shanghai Jiao Tong UniversityShanghai 200240China

Recently generation of strong magnetic(B)fields has been demonstrated in capacitor coils heated by high power laser pulses[*** et al.,***.3,1170(2013)].This paper will present a direct measurement of B field generated with an open-ended coil target driven by a nanosecond laser pulse using ultrafast proton *** radiographs are analyzed with particle-tracing *** B field at the coil center is inferred to be ~50 T at an irradiance of ~5×10^(14) W·cm^(-2).The B field generation is attributed to the background cold electron flow pointing to the laser focal spot,where a target potential is induced due to the escape of energetic electrons.

关键词： Strong magnetic field Laser-driven coil targets proton radiography