Particle Trajectory Error in Finite Element Particle-in-Cell Kinetic Plasma Simulations

Particle-In-Cell (PIC) algorithms are widely used for kinetic plasma simulations. In PIC algorithms, it's crucial to understand the resultant approximation errors due to the underlying space and time field discretization. Here, we examine the error in particle trajectories produced by a finite-element (FE) based PIC algorithm on unstructured meshes. We study the convergence of such error against two basic parameters: the FE mesh resolution and the matrix solver approximation.