High Intensity Laser Plasma Interactions, Ultrafast X-ray sources and Advanced Ignition Laser Fusion Energy

高强度激光等离子体相互作用、超快 X 射线源和先进点火激光聚变能

• 批准号: RGPIN-2014-05736
• 负责人: Fedosejevs, Robert
• 金额: $ 5.1万
• 依托单位: University of Alberta
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=588590
• 关键词: Intensity; Laser; Plasma; Interactions; Ultrafast

High intensity femtosecond laser pulses when focused to relativistic intensities (I > 1018 W/cm2 where the oscillatory velocity of free electrons in the focused laser radiation field approaches the speed of light) hold the promise of many exciting developments in the generation of advanced x-ray, particle and radioisotope sources. Two distinct approaches, thin foil targets and gas targets, for the generation of MeV energy electrons, protons and ions, are being pursued which in turn can be used for the generation of ultrashort bursts of x-rays and the generation of radioisotopes. All of these processes require an understanding of high intensity laser-plasma interactions in this strongly nonlinear regime. In addition, understanding and optimizing the generation mechanisms of these processes are important for the application to fast ignition laser fusion energy where the MeV energy electrons or protons can be used as an ignition spark to ignite the fusion reactions at the edge of a compressed fuel pellet, reducing the over laser energy requirements from multi-Megajoules to sub Megajoule for a potential laser fusion reactor. This could significantly reduce the cost and engineering development time for future laser fusion reactors. The present research proposal will continue ongoing research on the exploration of a number of areas of intermediate to high energy laser-plasma interaction physics including: 1) Wakefield acceleration of electrons up to GeV energies using 0.1 – 1 PW laser pulses, 2) keV x-ray betatron radiation generation from laser wakefield accelerated electrons and applications in femtosecond probing of plasmas, 3) development of femtosecond x-ray and gamma ray sources based on the use of undulators, high energy Bremssthralung from high-Z targets and inverse Compton scattering from MeV to GeV laser produced electron bunches, 4) MeV Proton generation from foil and gas targets and the production of radioisotopes for medical applications, 5) picosecond time resolved radiographic probing of plasma interaction using laser produced electron and proton jets, 6) Optimization of MeV electron and proton generation and transport studies for fast ignition applications and 7) Development of a new class of high efficiency laser driver systems based on diode pumped cryogenically cooled Yb:YAG and Yb:CaF2 ceramic crystals which could be the building block for future high efficiency and repetition rate fusion energy drivers. The wakefield generation of electrons will be optimized to producing mulit-GeV, quasi-monochromatic, low divergence electron bunches with applications in Betatron, synchrotron and Bremsstrahlung production of x-rays to gamma rays. This will put Canada on the forefront of high energy electron generation and acceleration using techniques which eventually could be used to scale TeV particle accelerators from tens of kilometers to hundreds of metres and potentially build small scale soft x-ray free electron lasers. The generation of multi-MeV protons and radioisotopes on demand could lead to compact proton cancer treatment sources and turnkey radioisotope supply systems located at major hospitals instead of at national accelerator or reactor facilities. The fast ignition technique and newer shock ignition technique together with the development of 20% efficiency ceramic based laser systems could be a critical technology for accelerating the development of fusion reactors on a 20 year time scale rather than the 40 year timescale of the past. Clean, universally available, environmentally safe, green-house-gas-free fusion energy is the ultimate solution for mankind’s large scale energy needs in the future and we should be vigorously exploring all options to bring fusion energy on line as soon as possible.

高强度飞秒激光脉冲当聚焦到相对论强度时（I > 1018 W/cm2，其中聚焦激光辐射场中自由电子的振荡速度接近光速）有望在先进 x- 的产生中实现许多令人兴奋的发展正在寻求两种不同的方法，即薄箔靶和气体靶，用于产生 MeV 能量电子、质子和离子，而这两种方法又可用于X射线超短爆发和放射性同位素的产生所有这些过程都需要了解这种强非线性状态下的高强度激光-等离子体相互作用。此外，了解和优化这些过程的产生机制也很重要。快速点火激光聚变能源的应用，其中兆电子伏能量的电子或质子可以用作点火火花来点燃压缩燃料芯块边缘的聚变反应，从而减少对激光能量的过度需求对于潜在的激光聚变反应堆，这可以显着减少未来激光聚变反应堆的成本和工程开发时间，目前的研究计划将继续对许多中高能领域的探索进行研究。激光-等离子体相互作用物理包括：1) 使用 0.1 – 1 PW 激光脉冲对高达 GeV 能量的电子进行尾流加速，2) 激光尾流加速电子产生 keV X 射线电子感应加速器辐射和应用在等离子体的飞秒探测中，3）基于使用波荡器、来自高 Z 目标的高能轫致辐射以及从 MeV 到 GeV 激光产生的电子束的逆康普顿散射来开发飞秒 X 射线和伽马射线源，4）MeV 质子从箔和气体靶材生成以及用于医疗应用的放射性同位素的生产，5) 使用激光产生的电子和质子对等离子体相互作用进行皮秒时间分辨放射线探测6) 优化 MeV 电子和质子生成以及快速点火应用的传输研究，7) 开发基于二极管泵浦低温冷却 Yb:YAG 和 Yb:CaF2 陶瓷晶体的新型高效激光驱动器系统未来高效率和重复率聚变能量驱动器的构建模块将优化电子尾场生成，以产生多GeV、准单色、低发散电子束。在 Betatron、同步加速器和轫致辐射生产 X 射线到伽马射线方面的应用，这将使加拿大处于高能电子产生和加速技术的前沿，这些技术最终可用于将 TeV 粒子加速器从数十公里扩展到数百公里。米并有可能建造小型软 X 射线电子激光器 按需产生多 MeV 质子和放射性同位素可能会导致紧凑的质子癌症治疗源和交钥匙放射性同位素供应。系统位于主要医院而不是国家加速器或反应堆设施中 快速点火技术和更新的冲击点火技术以及 20% 效率陶瓷基激光系统的开发可能是加速 20 核聚变反应堆发展的关键技术。清洁、普遍可用、环境安全、无温室气体的聚变能源是人类未来和大规模能源需求的最终解决方案。我们应该积极探索各种选择，尽快实现聚变能发电。