Graphical Representation of Particle Trajectories in a Moving Reference System

A graphical method is derived for the analysis of microwave electron tubes, ion accelerators etc., which refers particle positions and velocities to a moving reference system. If the forces are dependent on time only, the trajectories are transformed into straight lines. For inhomogeneous fields an approximation procedure applies. To demonstrate the capabilities of this method a brief treatment of the transit time phenomena in cavity triodes is outlined.