Three-dimensional continuous modeling of beam-electron cloud interaction: Comparison with analytic models and predictions for the present and future circular machines

Abstract

Long-term beam-electron cloud interaction is modeled with a three-dimensional parallel continuous model originally developed for plasma wakefield acceleration modeling. The simulation results are compared with the two-macroparticle model for strong head-tail instability. The two-macroparticle model captures some of the instability features of the beam; however, this model is too simple to accurately describe the complex nature of the beam-cloud interaction. The effects of dipole magnets on the horizontal and vertical beam size are discussed. The dipole magnets have stabilizing effect and reduce the beam spot size growth especially in the horizontal plane. The code is then used to model and make predictions for the beam dynamics in the presence of an electron cloud for several present and future circular machines around the world.