Laser Wakefield Acceleration at KHz Repetition Rate

一个非常强大的激光可以通过与一种被称为等离子体的物质状态相互作用来将电子加速到高能量，等离子体是一种带电粒子的电离气体。激光通过在等离子体中产生波来实现这一点，就像船在水中推进一样，电子可以在上面冲浪并被加速到高能量。在这个特定的项目中，激光脉冲将被控制，这些波的结构将在时间和空间上被绘制出来，两者都具有前所未有的精度。这些技术应该有助于紧凑型粒子加速器的发展。加速器每年代表着30亿美元的市场，但它们的整体影响甚至更大，因为它们被用于从癌症治疗到飞机机翼成像压力的各个领域。因此，紧凑和廉价的加速器的发展很可能在经济和技术上产生重大影响。该研究项目将利用位于密歇根大学安娜堡分校的相对论强度（~10^19 W /平方厘米，35 fs）激光的高重复率，“lambda -cube”，实现激光传播和尾流场形成的独特测量，对激光尾流场加速施加前所未有的控制，并产生高达10 MeV，持续时间为几fs的电子束，频率为0.5 kHz。利用密歇根大学在脉冲压缩和反馈控制方面取得的进展，利用lambda立方激光器将产生稳定的、高质量的、高达10 MeV、0.5 kHz重复率的相对论电子束。5fs脉冲将用作等离子体尾流场结构的超快4D探针，允许对加速器结构进行独特的层析成像表征。

A very powerful laser can be used to accelerate electrons to high energies by interacting with a state of matter known as a plasma, an ionized gas of charged particles. The laser achieves this by creating waves in the plasma, like a boat pushing through water, on which the electrons can surf and be accelerated to high energies. In this specific project the pulse of laser light will be controlled and the structure of these waves mapped out in time and space, both with unprecedented precision. These techniques should help the development of compact particle accelerators. Accelerators represent a $3B per year market, but their overall impact is even greater since they find use in everything from cancer therapy to imaging stresses in aircraft wings. Thus, the development of compact and cheap accelerators is likely to have a significant impact both economically and technologically.The research project will use the high repetition rate of the relativistic intensity (~10^19 W per square cm, 35 fs) laser, "Lambda-cubed", located on campus at the University of Michigan - Ann Arbor to enable unique measurements of laser propagation and wakefield formation, to exert unprecedented control of laser wakefield acceleration, and to generate up to 10 MeV, few fs duration electron beams at 0.5 kHz. Stable, high quality relativistic electron beams at up to 10 MeV at 0.5 kHz repetition rate using the Lambda-cubed laser will be generated by making use of advances in pulse compression and feedback control made at the University of Michigan. A 5 fs pulse will be used as an ultrafast 4D probe of the plasma wakefield structure, allowing unique tomographic characterization of the accelerator structure.