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A quantitative method for calculating irradiation area of laser target designator
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作者 ZHANG Jiandong HUANG Zhiyi SHI Guoqing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第4期633-641,共9页
In laser-guided bomb attacking process,the target indication from the laser target designator is the premise for the bomb to hit the target accurately.Considering the lack of quantitative study of the irradiation area... In laser-guided bomb attacking process,the target indication from the laser target designator is the premise for the bomb to hit the target accurately.Considering the lack of quantitative study of the irradiation area of the laser target designator,this paper,based on the existing aircraft motion model and the laser transmission model,uses two aircraft as respectively the carrier of the laser-guided bomb and the carrier of the laser designator and proposes a method to calculate the global irradiation area of the airborne laser designator.By using the proposed algorithm,the global irradiation area when attacking a large flat target or a large spherical target is simulated respectively.Finally,according to the simulation results,the influences of different factors on the shapes of the irradiation area are discussed in detail. 展开更多
关键词 laser-guided BOMB IRRADIATION area laser target designator SEMI-ACTIVE guidance
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A High-Resolution Measurement Method for Inner and Outer 3D Surface Profiles of Laser Fusion Targets Using a Laser Differential Confocal–Atomic Force Probe Technique
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作者 Weiqian Zhao Zihao Liu Lirong Qiu 《Engineering》 SCIE EI CAS CSCD 2024年第10期51-60,共10页
The high-resolution and nondestructive co-reference measurement of the inner and outer threedimensional(3D)surface profiles of laser fusion targets is difficult to achieve.In this study,we propose a laser differential... The high-resolution and nondestructive co-reference measurement of the inner and outer threedimensional(3D)surface profiles of laser fusion targets is difficult to achieve.In this study,we propose a laser differential confocal(LDC)–atomic force probe(AFP)method to measure the inner and outer 3D surface profiles of laser fusion targets at a high resolution.This method utilizes the LDC method to detect the deflection of the AFP and exploits the high spatial resolution of the AFP to enhance the spatial resolution of the outer profile measurement.Nondestructive and co-reference measurements of the inner profile of a target were achieved using the tomographic characteristics of the LDC method.Furthermore,by combining multiple repositionings of the target using a horizontal slewing shaft,the inner and outer 3D surface profiles of the target were obtained,along with a power spectrum assessment of the entire surface.The experimental results revealed that the respective axial and lateral resolutions of the outer profile measurement were 0.5 and 1.3 nm,while the respective axial and lateral resolutions of the inner profile measurement were 2.0 nm and approximately 400.0 nm.The repeatabilities of the rootmean-square deviation measurements for the outer and inner profiles of the target were 2.6 and 2.4 nm,respectively.We believe our study provides a promising method for the high-resolution and nondestructive co-reference measurement of the inner and outer 3D profiles of laser fusion targets. 展开更多
关键词 laser fusion targets laser differential confocal-atomic force probe HIGH-RESOLUTION Nondestructive Co-reference
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Transmission Degradation of Femtosecond Laser Pulses in Opened Cone Targets 被引量:1
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作者 LIU Feng LIN Xiaoxuan +14 位作者 LIU Bicheng DING Wenjun DU Fei LI Yutong MA Jinglong LIU Xiaolong SHENG Zhengming CHEN Liming LU Xin DONG Quanli WANG Weimin WANG Zhaohua WEI Zhiyi CHEN Jiaer ZHANG Jie 《Plasma Science and Technology》 SCIE EI CAS CSCD 2012年第1期24-27,共4页
Irradiated by femtosecond laser pulses with different energies, opened cone targets behave very differently in the transmission of incident laser pulses. The targets, each with an opening angle of 71° and an open... Irradiated by femtosecond laser pulses with different energies, opened cone targets behave very differently in the transmission of incident laser pulses. The targets, each with an opening angle of 71° and an opening of 5 μm, are fabricated using standard semiconductor technology. When the incident laser energy is low and no pre-plasma is generated on the side walls of the cones, the cone target acts like an optical device to reflect the laser pulse, and 15% of the laser energy can be transmitted through the cones. In contrast, when the incident laser energy is high enough to generate pre-plasmas by the pre-pulse of the main pulse that fills the inner cone, the cone with the plasmas will block the transmission of the laser, which leads to a decrease in laser transmission compared with the low-energy case with no plasma. Simulation results using optical software in the low-energy case, and using the particle-in-cell code in the high-energy case, are primarily in agreement with the experimental results. 展开更多
关键词 femtosecond laser pulse cone target transmission ratio
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High-Yield High-Efficiency Positron Generation in High-Z Metal Targets Irradiated by Laser Produced Electrons from Near-Critical Density Plasmas 被引量:1
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作者 宋炜 胡荣豪 +7 位作者 寿寅任 弓正 余金清 林晨 马文君 赵研英 卢海洋 颜学庆 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第8期96-100,共5页
An improved indirect scheme for laser positron generation is proposed. The positron yields in high-ZZ metal targets irradiated by laser produced electrons from near-critical density plasmas and underdense plasma are i... An improved indirect scheme for laser positron generation is proposed. The positron yields in high-ZZ metal targets irradiated by laser produced electrons from near-critical density plasmas and underdense plasma are investigated numerically. It is found that the positron yield is mainly affected by the number of electrons of energies up to several hundreds of MeV. Using near-critical density targets for electron acceleration, the number of high energy electrons can be increased dramatically. Through start-to-end simulations, it is shown that up to 6.78×10106.78×1010 positrons can be generated with state-of-the-art Joule-class femtosecond laser systems. 展开更多
关键词 High-Yield High-Efficiency Positron Generation in High-Z Metal targets Irradiated by laser Produced Electrons from Near-Critical Density Plasmas DLA
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Ground target localization algorithm for semi-active laser terminalcorrection projectile 被引量:2
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作者 Xing-long LI Wen-jin YAO +2 位作者 Li-kun ZHU Xiao-ming WANG Ji-yan YU 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2016年第3期234-241,共8页
A target localization algorithm,which uses the measurement information from onboard GPS and onboard laser detector to acquire the target position,is proposed to obtain the accurate position of ground target in real ti... A target localization algorithm,which uses the measurement information from onboard GPS and onboard laser detector to acquire the target position,is proposed to obtain the accurate position of ground target in real time in the trajectory correction process of semi-active laser terminal correction projectile.A target localization model is established according to projectile position,attitude and line-of-sight angle.The effects of measurement errors of projectile position,attitude and line-of-sight angle on localization accuracy at different quadrant elevation angles are analyzed through Monte-Carlo simulation.The simulation results show that the measurement error of line-of-sight angle has the largest influence on the localization accuracy.The localization accuracy decreases with the increase in quadrant elevation angle.However,the maximum localization accuracy is less than 7 m.The proposed algorithm meets the accuracy and real-time requirements of target localization. 展开更多
关键词 SEMI-ACTIVE laser GUIDANCE TERMINAL correction PROJECTILE target LOCALIZATION LOCALIZATION accuracy
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Effects of Laser Ablation on Ceramic Superconducting Targets
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作者 沙维 《Rare Metals》 SCIE EI CAS CSCD 1994年第1期41-45,共5页
A scanning electron microscopy study of the morphology of laser ablated superconducting targets. bothYBaCuO and BipbSrCaCuO, was reported. The effects of laser ablation on target structures are illustratedto provide a... A scanning electron microscopy study of the morphology of laser ablated superconducting targets. bothYBaCuO and BipbSrCaCuO, was reported. The effects of laser ablation on target structures are illustratedto provide a basis for further quality control of laser ablation of superconducting thin films. 展开更多
关键词 laser ablation Superconducting target SEM YBACUO BIPBSRCACUO
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Algorithm for Multi-laser-target Tracking Based on Clustering Fusion
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作者 张立群 李言俊 张科 《Defence Technology(防务技术)》 SCIE EI CAS 2007年第1期28-32,共5页
Multi-laser-target tracking is an important subject in the field of signal processing of laser warners. A clustering method is applied to the measurement of laser warner, and the space-time fusion for measurements in ... Multi-laser-target tracking is an important subject in the field of signal processing of laser warners. A clustering method is applied to the measurement of laser warner, and the space-time fusion for measurements in the same cluster is accomplished. Real-time tracking of multi-laser-target and real-time picking of multi-laser-signal are introduced using data fusion of the measurements. A prototype device of the algorithm is built up. The results of experiments show that the algorithm is very effective. 展开更多
关键词 激光报警器 多目标跟踪 算法 聚类融合 信息处理
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Numerical Simulation on Laser Propulsion Capability of Polymer Target
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作者 Nanlei Li Jifei Ye Weijing Zhou 《Optics and Photonics Journal》 2013年第2期11-14,共4页
A computational model of laser ablated polymer was established. Set the ablation criterion based on threshold energy. Put forward the polymer ablation criterion in the numerical model. It established the energy distri... A computational model of laser ablated polymer was established. Set the ablation criterion based on threshold energy. Put forward the polymer ablation criterion in the numerical model. It established the energy distribution equation to describe the laser ablation process. When the ablation products ejected, the target gained recoil impulse from ejection process. Get the ejection energy and the recoil momentum of target based on momentum conservation law. The numerical analysis model can reflect the propulsion capability of different polymer propellant, revealed the law of propulsion parameters in laser ablation process. 展开更多
关键词 laser PROPULSION laser Ablation POLYMER target
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Effect of Foil Target Thickness in Proton Acceleration Driven by an Ultra-Short Laser
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作者 路建新 兰小飞 +5 位作者 席晓峰 张海峰 张骥 王雷剑 汤秀章 王乃彦 《Plasma Science and Technology》 SCIE EI CAS CSCD 2015年第6期458-460,共3页
Proton acceleration experiments were carried out by a 1.2× 1018 W/cm2 ultra-short laser interaction with solid foil targets. The peak proton energy observed from an optimum target thickness of 7 μm in our experi... Proton acceleration experiments were carried out by a 1.2× 1018 W/cm2 ultra-short laser interaction with solid foil targets. The peak proton energy observed from an optimum target thickness of 7 μm in our experiments was 2.1 MeV. Peak proton energy and proton yield were investigated for different foil target thicknesses. It was shown that proton energy and conversion efficiency increased as the target became thinner, on one condition that the preplasma generated by the laser prepulse did not have enough shock energy and time to influence or destroy the target rear-surface. The existence of optimum foil thickness is due to the effect of the prepulse and hot electron transportation behavior on the foil target. 展开更多
关键词 ultra-short laser PROTON thin foil target target normal sheath acceleration
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Nd: YAG Laser Plasma Interaction with Metal Target
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作者 Ahmad Hadi Ali Noriah Bidin 《材料科学与工程(中英文版)》 2010年第2期14-18,共5页
关键词 激光等离子体相互作用 Nd:YAG激光 金属目标 尼康COOLPIX 激光诱导等离子体 脉冲持续时间 CCD数码相机 工件材料
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Arbitrary frequency stabilization of a diode laser based on visual Labview PID VI and sound card output 被引量:2
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作者 冯国胜 武寄洲 +5 位作者 王晓锋 郑宁宣 李玉清 马杰 肖连团 贾锁堂 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第10期248-251,共4页
We report a robust method of directly stabilizing a grating feedback diode laser to an arbitrary frequency in a large range. The error signal, induced from the difference between the frequency measured by a wavelength... We report a robust method of directly stabilizing a grating feedback diode laser to an arbitrary frequency in a large range. The error signal, induced from the difference between the frequency measured by a wavelength meter and the preset target frequency, is fed back to the piezoelectric transducer module of the diode laser via a sound card in the computer. A visual Labview procedure is developed to realize a feedback system. In our experiment the frequency drift of the diode laser is reduced to 8 MHz within 25 min. The robust scheme can be adapted to realize the arbitrary frequency stabilization for many other kinds of lasers. 展开更多
关键词 frequency stabilization Labview PID VI diode laser target frequency
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Generation of fast protons in moderate-intensity laser-plasma interaction from rear sheath 被引量:1
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作者 谭志新 黄永盛 +6 位作者 兰小飞 路建新 段晓礁 王雷剑 杨大为 郭士伦 王乃彦 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第5期399-405,共7页
Forward fast protons are generated by the moderate-intensity laser-foil interaction. Protons with maximum energy 190 keV are measured by using magnetic spectrometer and CR-39 solid state track detectors along the dire... Forward fast protons are generated by the moderate-intensity laser-foil interaction. Protons with maximum energy 190 keV are measured by using magnetic spectrometer and CR-39 solid state track detectors along the direction normal to the rear surface. The experimental results are also modeled by the paxticle-in-cell method, investigating the timevarying electron temperature and the rear sheath field. The temporal and spatial structure of the sheath electrical field, revealed in the simulation, suggests that these protons are accelerated by target normal sheath acceleration (TNSA) mechanism. 展开更多
关键词 laser proton acceleration target normal sheath acceleration
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Non-contact angle measurement based on parallel multiplex laser feedback interferometry 被引量:4
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作者 张松 谈宜东 张书练 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第11期320-324,共5页
We present a novel precise angle measurement scheme based on parallel multiplex laser feedback interferometry (PLFI), which outputs two parallel laser beams and thus their displacement difference reflects the angle ... We present a novel precise angle measurement scheme based on parallel multiplex laser feedback interferometry (PLFI), which outputs two parallel laser beams and thus their displacement difference reflects the angle variation of the target. Due to its ultrahigh sensitivity to the feedback light, PLFI realizes the direct non-contact measurement of non- cooperative targets. Experimental results show that PLFI has an accuracy of 8" within a range of 1400". The yaw of a guide is also measured and the experimental results agree with those of the dual-frequency laser interferometer Agilent 5529A. 展开更多
关键词 laser feedback angle measurement non-cooperative targets
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Generation and characterization of millimeter-scale plasmas for the research of laser plasma interactions on Shenguang-Ⅲ prototype 被引量:3
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作者 李志超 郑坚 +10 位作者 丁永坤 尹强 蒋小华 李三伟 郭亮 杨冬 王哲斌 章欢 刘永刚 詹夏宇 唐琦 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第12期368-372,共5页
In order to produce millimeter-scale plasmas for the research of laser-plasma interactions (LPIs), gasbag target is designed and tested on Shenguang-III prototype laser facility. The x-ray pinhole images show that m... In order to produce millimeter-scale plasmas for the research of laser-plasma interactions (LPIs), gasbag target is designed and tested on Shenguang-III prototype laser facility. The x-ray pinhole images show that millimeter-scale plasmas are produced with the gasbag. The electron temperature inferred from the stimulated Raman scattering (SRS) spectrum is about 1.6 keV. The SRS spectrum also indicates that the electron density has a fiat region within the duration of 200 ps. The obvious differences between the results of the gasbag and that of the void half hohlraum show the feasibility of the gasbag target in creating millimeter-scale plasmas. The LPIs in these millimeter-scale plasmas may partially mimic those in the ignition condition because the duration of the existence of a flat plasma density is much larger than the growth time of the two main instabilities, i.e., SRS and stimulated Brillouin scattering (SBS). So we make the conclusion that the gasbag target can be used to research the large-scale LPIs. 展开更多
关键词 gasbag target large scale laser plasma interaction stimulated Raman scattering
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Proton Acceleration Driven by High-Intensity Ultraviolet Laser Interaction with a Gold Foil 被引量:1
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作者 路建新 兰小飞 +4 位作者 王雷剑 席晓峰 黄永盛 汤秀章 王乃彦 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第9期863-865,共3页
Proton acceleration induced by a high-intensity ultraviolet laser interaction with a thin foil target was studied on an ultra-short KrF laser amplifier called LLG50 in China Institute of Atomic Energy (CIAE). The ul... Proton acceleration induced by a high-intensity ultraviolet laser interaction with a thin foil target was studied on an ultra-short KrF laser amplifier called LLG50 in China Institute of Atomic Energy (CIAE). The ultraviolet laser produced pulses with a high-contrast of 109, duration of 500 fs and energy of 30 mJ. The p-polarized laser was focused on a 2.1 #m gold foil by an off-axis parabola mirror (OAP) at an incident angle of 45°. The laser intensity was 1.2× 1017 W/cm2. The divergence angle for proton energy of 265 keV or higher was 30°, which was recorded by a CR39 detector covered with 2 μm aluminum foil in the target normal direction. The maximum proton energy recorded by a CR39 detector covered with a 4 μm aluminum foil was 440 keV, and the proton energy spectrum was measured by a proton spectrometer. The ultraviolet laser acquires a relatively lower hot electron temperature, which can be ascribed to the proportional relationship of Iλ2, but a higher hot electron density because of the higher laser absorption and critical density. Higher electron density availed to strengthen the sheath electric field, and increased the proton acceleration. 展开更多
关键词 ULTRAVIOLET ultra-short laser PROTON thin foil target target normal sheathacceleration
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Development of Debris-free Laser Plasma Sources for EUV Lithography in CIOMP 被引量:1
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作者 CHEN Bo, NI Qi liang,CAO Jian lin (State Key Laboratory of Applied Optics,Changchun Institute of Optics, Fine Mechanics and Physics,Chinese Academy of Sciences, Changchun 130022, China) 《光学精密工程》 EI CAS CSCD 2001年第5期442-445,共4页
We have been developing debris-free laser plasma sources for EUV lithography since 1996. Two types of debris-free sources, such as cryogenic target and gas-puff target laser plasma sources, were designed and built up ... We have been developing debris-free laser plasma sources for EUV lithography since 1996. Two types of debris-free sources, such as cryogenic target and gas-puff target laser plasma sources, were designed and built up in CIOMP. EUV radiation spectra of the sources with a variety of targets have been obtained by different ways. 展开更多
关键词 EUV LITHOGRAPHY laser plasma DEBRIS - free CRYOGENIC target gas - PUFF target
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Doppler shift of a laser pulse beam scattered by a rotating cone and cylinder
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作者 王保平 王明军 +2 位作者 吴振森 李应乐 向宁静 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第5期60-65,共6页
Based on laser radar equations, a Doppler shift model of a laser pulse beam scattered by a rotating arbitrary convex target is reported in this paper. The boundary relations between an incident pulse beam and the dete... Based on laser radar equations, a Doppler shift model of a laser pulse beam scattered by a rotating arbitrary convex target is reported in this paper. The boundary relations between an incident pulse beam and the detected area elements are analyzed by geometric methods. The Doppler shift characteristics of the rotating cone and cylinder are discussed and the difference between the laser pulse beam and the plane wave scattered from the same rotating target is compared accordingly. Numerical simulations show that the Doppler shift is tightly relevant to their dimensions, speeds, and so on. In the same incidence conditions, the pulse beam and plane wave have difference peak values and the same Doppler shift bandwidth. If the waist radius of the pulse beam is larger, the peak value is higher, and the Doppler shifts are proportional to the speed of the rotating target. By virtue of our theoretical model, we probe into the scattered characteristics of the Doppler shifts of a laser pulse beam, which would benefit target identification in national defense. 展开更多
关键词 scattered characteristics of laser pulse beams Doppler shift laser radar target identification
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High Accuracy and Real-Time Gated Viewing Laser Radar
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作者 Dong Li Hua-Jun Yang Shan-Pei Zhou 《Journal of Electronic Science and Technology》 CAS 2011年第3期261-264,共4页
A gated viewing laser radar has an excellent performance in underwater low light level imaging, and it also provides a viable solution to inhibit backscattering. In this paper, a gated viewing imaging system according... A gated viewing laser radar has an excellent performance in underwater low light level imaging, and it also provides a viable solution to inhibit backscattering. In this paper, a gated viewing imaging system according to the demand for real-time imaging is presented, and then the simulation is used to analyze the performance of the real-time gated viewing system. The range accuracy performance is limited by the slice number, the width of gate, the delay time step, the initial delay time, as well as the system noise and atmospheric turbulence. The simulation results indicate that the highest range accuracy can be achieved when the system works with the optimal parameters. Finally, how to choose the optimal parameters has been researched. 展开更多
关键词 Index Terms Gated viewing range accuracy real-time laser radar target detection.
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Generation of high quality ion beams through the stable radiation pressure acceleration of the near critical density target 被引量:1
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作者 洪学仁 周伟军 +5 位作者 谢柏松 杨阳 王莉 田建民 唐荣安 段文山 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第6期234-243,共10页
In order to generate high quality ion beams through the stable radiation pressure acceleration(RPA) of the near critical density(NCD) target, we propose a new type of target where an ultra-thin high density(HD) ... In order to generate high quality ion beams through the stable radiation pressure acceleration(RPA) of the near critical density(NCD) target, we propose a new type of target where an ultra-thin high density(HD) layer is attached to the front surface of an NCD target, which has a preferable self-supporting property in the RPA experiments than the ultra-thin foil target. It is found that in one-dimensional particle-in-cell(PIC) simulation, by the block of the HD layer in the new target,there emerges the hole-boring process rather than propagation in the NCD layer when the intense laser pulse impinges on this target. As a result, a typical RPA structure that the compressed electron layer overlaps the ion layer as a whole is formed and a high quality ion beam is obtained, e.g., a circularly polarized laser pulse with normalized amplitude a0= 120 impinges on this new target and a 1.2 GeV monoenergetic ion beam is generated through the RPA of the NCD layer. Similar results are also found in the two-dimensional PIC simulation. 展开更多
关键词 laser plasma interaction radiation pressure acceleration near critical density target
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拍瓦激光驱动纳米刷靶高品质质子束的产生
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作者 杨月 孙斌 +16 位作者 邓志刚 滕建 贺书凯 张博 王少义 张智猛 于明海 温家星 谭放 闫永宏 王子涛 周凯南 陈忠靖 吴玉迟 周维民 谷渝秋 赵宗清 《强激光与粒子束》 CAS CSCD 北大核心 2024年第1期112-116,共5页
超强激光加速产生的高能质子束源在基础物理研究、材料科学、生物医疗等领域具有广泛应用前景。基于激光聚变研究中心的SILEX-II装置,开展了高对比度飞秒激光驱动纳米刷靶质子加速实验研究。采用等离子体镜技术进一步提升激光对比度,有... 超强激光加速产生的高能质子束源在基础物理研究、材料科学、生物医疗等领域具有广泛应用前景。基于激光聚变研究中心的SILEX-II装置,开展了高对比度飞秒激光驱动纳米刷靶质子加速实验研究。采用等离子体镜技术进一步提升激光对比度,有效降低了预脉冲对纳米刷靶结构的影响。相比于平面靶,采用纳米刷靶质子截止能量提高到1.5倍,质子束产额增加近一个量级,成功验证了超高功率密度下纳米刷靶对激光离子加速的增强效果,并且有效提升了质子束空间分布的均匀性。研究结果为高品质质子束源的产生和应用提供了技术途径。 展开更多
关键词 纳米刷靶 激光离子加速 等离子体镜 高品质质子束
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