Andonian G, Williams O, Barber S, Bruhwiler D, Favier P, Fedurin M, Fitzmorris K, Fukasawa A, Hoang P, Kusche K, Naranjo B, O'Shea B, Stoltz P, Swinson C, Valloni A, Rosenzweig J B
Department of Physics and Astronomy, University of California at Los Angeles (UCLA), Los Angeles, California 90095, USA.
University of Colorado at Boulder, Center for Integrated Plasma Studies, Boulder, Colorado 80309, USA and RadiaSoft LLC, Boulder, Colorado 80304, USA.
Phys Rev Lett. 2014 Dec 31;113(26):264801. doi: 10.1103/PhysRevLett.113.264801. Epub 2014 Dec 30.
We report experimental measurements of narrow-band, single-mode excitation, and drive beam energy modulation, in a dielectric wakefield accelerating structure with planar geometry and Bragg-reflector boundaries. A short, relativistic electron beam (∼1 ps) with moderate charge (∼100 pC) is used to drive the wakefields in the structure. The fundamental mode of the structure is reinforced by constructive interference in the alternating dielectric layers at the boundary, and is characterized by the spectral analysis of the emitted coherent Cherenkov radiation signal. Data analysis shows a narrow-band peak at 210 GHz corresponding to the fundamental mode of the structure. Simulations in both 2D and 3D provide insight into the propagating fields and reproduction of the electron beams dynamics observables and emitted radiation characteristics.
我们报告了在具有平面几何形状和布拉格反射器边界的介质尾场加速结构中，对窄带、单模激发和驱动束能量调制的实验测量。使用具有中等电荷量（约100 pC）的短相对论电子束（约1 ps）来驱动该结构中的尾场。结构的基模通过边界处交替介电层中的相长干涉得到增强，并通过对发射的相干切伦科夫辐射信号进行光谱分析来表征。数据分析显示在210 GHz处有一个对应于该结构基模的窄带峰值。二维和三维模拟为传播场以及电子束动力学可观测量和发射辐射特性的再现提供了深入了解。
