Macroparticles
Macroparticles are a computational representation used in kinetic simulations to model many physical particles with a single tracked entity. Each macroparticle stands for a group of real particles and carries a statistical weight that scales its charge and mass relative to a single particle. In common formulations, the macroparticle’s position and velocity describe the center of its group in phase space, while the macroparticle charge q and mass m are given by q = w q0 and m = w m0, where w is the weight and q0, m0 are the charge and mass of the species being modeled.
In particle-in-cell and related methods, the simulation domain is discretized on a spatial grid. Macroparticles move
Macroparticles enable efficient modeling of plasmas, charged beams, and other collective systems where full tracking of
Limitations include statistical noise from finite sampling, numerical heating, and weight-induced inconsistencies if not managed carefully.