激光加速器中的靶科学与技术  

Science and technologies in targets for laser accelerators

作　　者：马文君 Wenjun Ma(Institute of Heavy lon Physics,School of Physics,Peking University,Beijing 100871,China;State Key Laboratory of Nuclear Physics and Technology,Beijing 100871,China;Beijing Laser Acceleration Innovation Center,Beijing 101400,China)

机构地区：[1]北京大学物理学院重离子物理研究所,北京100871 [2]核物理与核技术国家重点实验室,北京100871 [3]北京激光加速创新中心,北京101400

出　　处：《科学通报》2023年第9期1047-1053,共7页Chinese Science Bulletin

基　　金：国家自然科学基金(12225501,11921006)资助。

摘　　要：激光加速器通过激光打靶产生高能带电粒子,是一种极具潜力的新型加速器.与“靶”相关的科学与技术,对激光加速器性能的提升、设备的实用化与普及起着至关重要的作用.本文概述靶科学与技术对激光加速器的重要意义,探讨其中的关键问题,着重介绍北京大学重离子物理研究所研究团队在相关领域取得的进展.通过与纳米科技结合,我们创立发展了碳纳米管靶体系,成功解决了临界密度靶难题;设计并构建双层纳米靶,实现了重离子级联加速过程,解决了短脉冲激光加速重离子/超重离子时高效电离与长时间加速难以兼得的瓶颈问题,创纪录地获得了580 MeV碳离子与1.2 GeV金离子;攻克了高品质靶材批量制备、靶材损伤阈值测控、高精度瞄靶、重频打靶等关键技术,有力推动了激光离子加速器实用化进程.Laser plasma acceleration(also referred to as laser acceleration)employs ultra-strong electric fields generated when an ultra-intense laser pulse interacts with the plasma to accelerate charged particles.As a promising novel acceleration method,its acceleration gradient can be 10^(3)-10^(6) times that of conventional accelerators.Laser accelerators based on the laser acceleration process can not only generate ultra-short pulse particle/photon beams for fundamental research,but also provide high-energy protons/heavy ions for tumor radiotherapy devices,benefiting people's lives and health.Under the strong national investment around the world,basic and applied research related to laser accelerators has developed rapidly inrecentyears.Unlike conventional accelerators,which use macroscopic electromagnetic fields to accelerate particles in a vacuum,the laser acceleration process is realized by shooting targets with laser pulses.The scientific and technical problems related to the“target”are the core problems of the laser accelerator.In order to build an accelerator that can stably output high-energy particle beams,on the one hand,developing new target systems and deeply studying laser acceleration physics is highly necessary.On the other hand,overcoming a large number of key technical issues related to the preparation and characterization of targets and shooting is also very crucial.This paper gives an introduction to the key problems in the science and technologies for laser accelerators and highlights the progress in this field made by our team at the Institute of Heavy Ion Physics of Peking University.By exploiting nanotechnology and nanomaterials,we developed novel targets made of carbon nanotubes,which can serve as long-awaited perfect near-critical-density(NCD)targets.With such targets,we observed the laser focusing and pulse steepening in NCD plasmas for relativistic laser pulses for the first time.We also successfully achieved cascaded ion acceleration scheme by designing and building double-layer CNT targe

关 键 词：粒子加速器 激光加速器 激光等离子体加速 靶科学与技术 

分 类 号：TL50[核科学技术—核技术及应用]