Dr. Yelong Wei venia legendi lecture "Investigations into X-band dielectric accelerating structures for future linear accelerators"

As a part of Horizon 2020 ERA Chair project MATTER, there will be a Venia Legendi on 23th of January at 14.15 held by ERA Chair holder candidate Dr. Yelong Wei who is Senior Fellow in European Organization for Nuclear Research (CERN). Lecture will be held at Institute of Technology, Nooruse 1-121.

His main research focus is in the numerical study and wakefield measurement for X-band RF accelerating structures, investigations into the X-band dielectric disk accelerating structures for linear collider applications, fabrication and experimental studies on the optimized X-band dielectric accelerating structures.

A potential alternative to conventional disk-loaded copper structures is dielectric-loaded accelerating (DLA) structures, which utilizes dielectrics to slow down the phase velocity of travelling wave in the vacuum channel. A DLA structure comprises a simple geometry where a dielectric tube is surrounded by a conducting cylinder. The simplicity of the DLA structure offers a great advantage for RF-driven accelerating structures as compared with conventional metal structures which demand extremely tight fabrication tolerances. This is of a great importance in the case of linear collider where tens of thousands accelerating structures have to be built.

This talk numerically investigates an X-band dielectric disk accelerating (DDA) structure operating at a higher-order TM02-π mode. This accelerating structure consists of dielectric disks with irises periodically arranged in a metallic enclosure. Through optimizations, the power loss on the metallic wall can be significantly reduced, thereby resulting in an extremely high quality factor and shunt impedance as compared to conventional RF accelerating structures. The geometry of regular and end cells is described in detail. Due to its wide bandwidth from dispersion curve, the maximum number of cells can be up to 250 without mode overlapping, which is also superior to those conventional RF accelerating structures. The wakefield studies on such a DDA structure are also presented. In addition, this talk also presents a novel design of matching section for coupling the high power from circular waveguide to dielectric-loaded waveguide accelerating structures, resulting in a very compact broadband and low RF field which has potential to go to very high power. Such a prototype is under fabrication with a collaboration of researchers from Argonne National Laboratory and Euclid Techlabs.

More information about ERA Chair MATTER is abailable in: https://matter.tuit.ut.ee/
ERA Chair MATTER has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 856705.

Contact name: Vahur Zadin
Contact e-mail: vahur.zadin@ut.ee
Location: Nooruse 1-121, Tartu