Document Type

Conference Paper

Publication Date






Conference Name

12th International Particle Accelerator Conference, May 24-28th, 2021, Campinas, Brazil


A new C++ custom element has been developed with the framework of General Particle Tracer (GPT) to simulate electron impact ionization of residual gas molecules. The custom element uses Monte-Carlo routines to determine both the ion production rate and the secondary electron kinetic energy based on user-defined gas densities and theoretical values for the ionization cross section and the secondary electron differential cross section. It then uses relativistic kinematics to track the secondary electron, the scattered electron, and the newly formed ion after ionization. The ion production rate and the secondary electron energy distribution determined by the custom element have been benchmarked against theoretical calculations and against simulations made using the simulation package IBSimu. While the custom element was originally built for particle accelerator simulations, it is readily extensible to other applications. The custom element will be described in detail and examples of applications at the Thomas Jefferson National Accelerator Facility will be presented for ion production in a DC high voltage photo-gun.


Published by JACoW Publishing under the terms of the Creative Commons Attribution 3.0 Unported (CC BY 3.0) license. Any further distribution of this work must maintain attribution to the author(s), the published article's title, publisher, and DOI.

Original Publication Citation

Yoskowitz, J. T., Krafft, G. A., Geer, S. B. v. d., Grames, J., Soto, R. M., & Lizarraga, C. A. V. (2021). Simulating electron impact ionization using a general particle tracer (GPT) custom element. 12th International Particle Accelerator Conference (2021), 24-28 May 2021, Campinas, Brazil.