Finite Element Analysis of Electrostatic Fields in Gas Ionization Chambers for Laser-Driven Proton Therapy

This paper presents a finite element analysis of the electrostatic field in gas ionization chambers used for beam diagnostics in laser-accelerated proton therapy systems. With the advent of laser-driven proton accelerators, such as the CLAPA-II project, there is a growing need for precise beam monitoring systems capable of handling high peak currents and large energy dispersion. Gas ionization chambers are widely employed for this purpose due to their reliability and accuracy. Using ANSYS software, this study establishes a detailed electrostatic finite element model of a multi-electrode ionization chamber. Key steps include model simplification, gas region definition, regional meshing, and solver selection. The analysis demonstrates the convergence of the electrostatic field solution and validates the model’s accuracy. The proposed modeling approach not only enhances computational efficiency but also facilitates interoperability with other simulation platforms such as Garfield++. This work provides a reliable foundation for optimizing ionization chamber design and improving beam diagnostic precision in advanced proton therapy applications.