RF breakdown limits the attainable acceleration gradient in normal conducting RF structures, challenging high-gradient operations. Recent experiments at the Argonne Wakefield Accelerator (AWA) suggests short RF pulses (a few nanoseconds) can mitigate this breakdown. We simulated dark current emission in the short-pulse regime to study breakdown initiators including field emission and...
Structure-based wakefield acceleration (SWFA) is a proposed concept to overcome limitations in conventional accelerators. This approach allows for the creation of short-input radiofrequency (rf) pulses, which have been empirically shown to reduce breakdown rates at a given gradient. Metamaterial structures with negative group velocity have shown promise in accelerator applications. A structure...
The generation of high spectral brilliance radiation with electron beam sources relies heavily on the qualities of the electron transverse emittance and its longitudinal compression which significantly affect X-ray generation efficiency in Inverse Compton Scattering. Designing and building such a system in a compact formfactor requires non-trivial solutions starting from electrons generation...
In this talk we will present results from high gradient structure testing of single, multi-cell and meter-scale accelerating structures. Structures were tested with a variety of fabrication techniques including brazing, diffusion bonding and clamped plated structures. Target gradients of 120 MeV/m were achieved and exceeded. Designs and performance of rf components (loads, windows, etc.) for...
This paper presents the final physics design of the THz wakefield acceleration experiment using three dielectric structure cross-sections at the Argonne Wakefield Accelerator (AWA) facility. The experiment will focus on multi-bunch excitation of wakefields, exploration of the wakefield transverse-force topology, and possibly support an experiment on energy recovery. This contribution discusses...
The global collaboration between PAL, NIU, ANL, and KU is ongoing to develop an electron beam-driven THz power generation and two-beam acceleration in SWFA. We successfully demonstrated the fabrication of a 0.2 THz structure and the characteristic of wakefield using the beam-based experimental measurement. of a 0.2 THz structure a few years ago. The success of a new fabrication method led us...
Because of their ability to produce high gradients, radiofrequency (RF) structures in the sub-terahertz (sub-THz) regime are of considerable interest in structure wakefield acceleration. These structures can be used to generate a high gradient and high efficiency wakefield, allowing for a low physical footprint. In the pursuit of a structure with these properties, we have designed and built a...