A Simulation Model for the FX-75 Relativistic Electron Beam Accelerator

A one-dimensional, time-dependent coaxial transmission line model is presented for analysis of the voltage, v(z,t), and current, i(z,t), response to an electron beam load for the FX-75 accelerator. The model consists of finite segments of coaxial transmission lines separated by lumped equivalent circuits representing the various abrupt discontinuity points. Each line segment is divided into two one-dimensional grids with a 0.1 nanosecond transit time grid separation for the backward and forward TEM waves. Results from program FXPULSE utilizing a thirty-eight line-load representation of the FX-75 accelerator for a time-invariant, high-impedance diode load show close agreement.