The high-precision energy spectrometry system, as a key electron beam diagnostic, enables accurate measurement of beam energy distribution and supports injector performance optimization. Beam collimation prior to the system affects measurement accuracy. For electron injectors operating at a few MeV, a high-precision spectrometry system based on the magnetic deflection method is developed, and an energy spectrum model is established to study the design and magnetic field optimization of the key dipole magnet (D-magnet) as well as the influence of upstream beam collimation on beam trajectory accuracy. Simulation results indicate that the optimized D-magnet enhances performance, and beam collimation analysis verifies effective trajectory control, improving system precision and providing technical support for high-precision energy measurements.
Zeng et al. (2026) studied this question.