Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, California 90095, USA.
SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA.
Nat Commun. 2016 Sep 14;7:12763. doi: 10.1038/ncomms12763.
There is urgent need to develop new acceleration techniques capable of exceeding gigaelectron-volt-per-metre (GeV m(-1)) gradients in order to enable future generations of both light sources and high-energy physics experiments. To address this need, short wavelength accelerators based on wakefields, where an intense relativistic electron beam radiates the demanded fields directly into the accelerator structure or medium, are currently under intense investigation. One such wakefield based accelerator, the dielectric wakefield accelerator, uses a dielectric lined-waveguide to support a wakefield used for acceleration. Here we show gradients of 1.347±0.020 GeV m(-1) using a dielectric wakefield accelerator of 15 cm length, with sub-millimetre transverse aperture, by measuring changes of the kinetic state of relativistic electron beams. We follow this measurement by demonstrating accelerating gradients of 320±17 MeV m(-1). Both measurements improve on previous measurements by and order of magnitude and show promise for dielectric wakefield accelerators as sources of high-energy electrons.
目前迫切需要开发新的加速技术，使其能够超过千兆电子伏特每米（GeV/m）的梯度，从而为未来的光源和高能物理实验提供支持。为了满足这一需求，目前正在对基于尾流场的短波长加速器进行深入研究，其中包括强烈相对论电子束将所需场直接辐射到加速器结构或介质中的加速器。基于尾流场的加速器之一，即介电尾流加速器，使用填充介质的波导来支持用于加速的尾流场。在这里，我们通过测量相对论电子束的动力学状态的变化，展示了使用长度为 15 厘米、亚毫米横向孔径的介电尾流加速器实现的 1.347±0.020 GeV/m 的梯度。在此测量之后，我们还展示了 320±17 MeV/m 的加速梯度。这两个测量结果都比以前的测量结果提高了一个数量级，为介电尾流加速器作为高能电子源的应用提供了前景。
