Calculation and analysis on electric field of high gradient insulator

Abstract

High gradient insulator (HGI) is one of the key technologies in dielectric wall accelerator (DWA). The electric field of HGI in different structures was calculated using finite element method (FEM). The effect of electrodes on electric field distribution was considered in modeling. The electric field of HGI was also compared with that of homogeneous insulator in the same thickness. In addition, we studied the field distribution differences when the outermost layer of HGI was individually insulation or metal. How the insulation layer dielectric constant and radio of insulation layer and metal layer influence the electric field of HGI was analyzed. The field intensity vector, the radial and axial field component of HGI surface was obtained. The study results indicate that the radial electric field plays an important role in micro-stack insulator. It not only changes the electron motion trace to suppress the secondary electron emission, but also emits electrons when electric field here is higher than some value. The research provides some references for micro-stack insulator design, and it’s also the foundation of further calculation on particle trace.