Relativistic Space-Charge Field Calculation by Interpolation-Based Treecode

Autor: Kan, Yi-Kai, Kärtner, Franz X., Borne, Sabine Le, Zemke, Jens-Peter M.
Rok vydání: 2022
Předmět:
Zdroj: Computer Physics Communications: 286, pp. 108668, 2023
Druh dokumentu: Working Paper
DOI: 10.1016/j.cpc.2023.108668
Popis: Space-charge effects are of great importance in particle accelerator physics. In the computational modeling, tree-based methods are increasingly used because of their effectiveness in handling non-uniform particle distributions and/or complex geometries. However, they are often formulated using an electrostatic force which is only a good approximation for low energy particle beams. For high energy, i.e., relativistic particle beams, the relativistic interaction kernel may need to be considered and the conventional treecode fails in this scenario. In this work, we formulate a treecode based on Lagrangian interpolation for computing the relativistic space-charge field. Two approaches are introduced to control the interpolation error. In the first approach, a modified admissibility condition is proposed for which the treecode can be used directly in the lab-frame. The second approach is based on the transformation of the particle beam to the rest-frame where the conventional admissibility condition can be used. Numerical simulation results using both methods will be compared and discussed.
Comment: 27 pages with 7 figures
Databáze: arXiv