Geant4-Based Simulation Of Charged Particle Deflection In Magnetic Fields For Beam Profiling In Proton And Electron Therapy

Abstract

Proton and electron therapy, offer advanced treatment options due to their precision in dose localization and ability to spare healthy tissues. This study investigates the deflection behavior and energy deposition profiles of electron and proton beams under transverse magnetic fields using Geant4 toolkit. Simulations were conducted using water phantoms embedded with tumors at shallow (1 cm), medium (5 cm), and deep (10 cm) depths. Electron beams (5–20 MeV) and proton beams (6–250 MeV) were analyzed under varying magnetic field strengths (up to 0.03 T for electrons and 0.3 T for protons). Energy deposition was scored in pre-tumor, tumor, and post-tumor regions. Geant4 results were validated against theoretical deflection angles derived from Lorentz force calculations. The results underscore the importance of tailoring charged particle therapy to tumor depth and location. Electron therapy is best suited for superficial tumors, while proton therapy offers superior spatial control for deep or anatomically complex targets.