3-D Electromagnetic Simulations forElectron Beam Positioning

In this paper, 3-D simulations have been carried out to position electron beam of high-power (60 kW, 60 kV, 1 A) linear electron gun. These simulations are highly significant for indirectly heated electron guns due to the presence of an additional electrode. In the inter-electrode space, particle trajectories, effective electron beam cross-section bombardment at solid cathode and electron beam emittance are crucial beam characteristics. Detailed 3-D electrostatic, electromagnetic and particle tracking simulations in inter-electrode region as well as in post-anode region have been successfully done for two parametric variations of electron gun. These include 1) Filament-solid cathode interspacing: Interelectrode region and 2) Magnetic coil current and corresponding magnetic field: Post-anode region. CST Studio Particle Tracking Module simulation software has been used, employing adaptive mesh refinement for fine meshing to ensure high accuracy results.