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
在激光血浆相互作用的离子加速上的一些笔记和评价被给，特别地为吃惊的含意，鞘并且可伸缩。一个简单模型被吃惊和鞘的联合为离子加速建议。在最大的离子精力和激光参数之间的获得的可伸缩的关系(力量，脉搏持续时间)也血浆参数(血浆密...在激光血浆相互作用的离子加速上的一些笔记和评价被给，特别地为吃惊的含意，鞘并且可伸缩。一个简单模型被吃惊和鞘的联合为离子加速建议。在最大的离子精力和激光参数之间的获得的可伸缩的关系(力量，脉搏持续时间)也血浆参数(血浆密度)，例如 E <SUB >离子，最大</SUB> P <SUP>7/12</SUP><SUB > L </SUB>, E <SUB >离子，最大</SUB>τ
<SUP>1/3</SUP><SUB > L </SUB>,和 E <SUB >离子，最大</SUB> n <SUP>2/3</SUP><SUB > e </SUB>,与以前的工作相比。模型和结果的一些缺乏和含意被讨论。展开更多
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
基金Project supported by the National Natural Science Foundation of China (Grant No. 10834008)the State Key Development Program for Basic Research of China (Grant No. 2006CB806004)
文摘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.
基金supported by the National Natural Science Foundation of China under Grant Nos. 10875015, 10834008 and partially by 10725521the New Century Excellent Talents in Universities (NCET) of China
文摘在激光血浆相互作用的离子加速上的一些笔记和评价被给，特别地为吃惊的含意，鞘并且可伸缩。一个简单模型被吃惊和鞘的联合为离子加速建议。在最大的离子精力和激光参数之间的获得的可伸缩的关系(力量，脉搏持续时间)也血浆参数(血浆密度)，例如 E <SUB >离子，最大</SUB> P <SUP>7/12</SUP><SUB > L </SUB>, E <SUB >离子，最大</SUB>τ
<SUP>1/3</SUP><SUB > L </SUB>,和 E <SUB >离子，最大</SUB> n <SUP>2/3</SUP><SUB > e </SUB>,与以前的工作相比。模型和结果的一些缺乏和含意被讨论。
基金supported by the Key Project of Chinese National Programs for Fundamental Research(973 Program)(No.2011CB808104)National Natural Science Foundation of China(Nos.11335013,11375276,11105234)
文摘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.
