Acceleration and focusing of positron bunch in a dielectric wakefield acceleratorwith plasma in transport channel

Abstract

The paper presents the results of numerical particle-in-cell simulation of the positron bunch focusing during acceleration in a plasma dielectric wakefield accelerator. The wakefield is excited by drive electron bunch in quartz dielectric tube, embedded in a cylindrical metal waveguide. The internal area of the dielectric tube is filled with plasma having in the general case the paraxial vacuum channel. Two different models of the plasma density radius-relationship are investigated: the homogeneous model and the inhomogeneous dependence characterized the capillary discharge. Results of the numerical particle-in-cell simulation show that a simultaneous acceleration and focusing of the test positron bunch in the wakefield is possible. The dependence of transport and acceleration of the positron bunch with change in the size of vacuum channel, waveguide length and the plasma density-radius model is studied.