Particle-in-cell plasma oscillations with 4 to 256 cells

Summary form only given. Questions arise on changing the numbers of grid cells used in our XES1 periodic electrostatic code, using first order (linear) weighting, with two electrons, excited in the fundamental model by an initial velocity. We present graphs of the two particles in space, E(x), rho(x), and phi(x) with 0<x<L. We start with a coarse grid of 4 cells, then 16, 64 and finally a fine grid of 256 cells. The two particles motion are periodic, initiated by =1, making for elliptic motion in space, and periods near 2pi, for omega set equal to 1 at t=0. The charge densities start as broad triangles, narrowing to fit one or two cells (spikes). The oscillation periods are close to 2pi in all runs, as shown in the final graph