Electromagnetic simulation study of dielectric wall accelerator structures

Two types of dielectric wall accelerator (DWA) structures, a bi-polar Blumlein line and zero integral pulse line (ZIP) structures were investigated. The high gradient insulator simulated by the particle in cell code confirms that it has little influence on the axial electric field. The results of simulations using CST microwave studio indicate how the axial electric field is formed, and the electric field waveforms agree with the theoretical one very well. The influence of layer-to-layer coupling in a ZIP structure is much smaller and the electric field waveform is much better. The axial of the Blumlein structure's electric field has better axial stability. From both of the above, it found that for a shorter pulse width, the axial electric field is much higher and the pulse stability and fidelity are much better. The CST simulation is very helpful for designing DWA structures. (authors)