Background In the study of X-ray generation via electron beam–target interactions, understanding the influence of target material parameters on the spatial-energy distribution of X-ray is essential for advancing X-ray source design and radiation protection.

Purpose This paper aims to systematically investigate the effects of target material, thickness, and inclination angle on X-ray energy spectra and spatial-energy distribution, thereby enriching the theoretical basis for X-ray source optimization and experimental radiation protection.

Methods Monte Carlo simulations were conducted to model the interaction of a 400 keV electron beam with Cu, Au, and Ta targets of varying thicknesses (20 μm to 200 μm). The bremsstrahlung spectra were calculated, and the spatial-energy distribution characteristics were further analyzed using a 40 μm Ta target under different inclination angles (0° to 45°) and electron beam offset angles.

Results The bremsstrahlung spectra exhibited photon energy peaks at approximately 20 keV (Cu), 80 keV (Au), and 60 keV (Ta), with maximum yields observed at thicknesses of 60 μm, 30 μm, and 40 μm, respectively. For the 40 μm Ta target, the spatial-energy distribution of the 60 keV spectrum showed a dumbbell-shaped pattern, with stronger energy distribution parallel to the incident direction. As the target inclination angle increased, the spectral probability from detection surfaces 1 to 20 first decreased and then increased. Increasing the electron beam offset angle reduced spectral probability and photon yield, while the overall energy distribution curve remained unchanged.

Conclusions Target material, thickness, and inclination angle significantly affect X-ray spectral characteristics and spatial distribution. The observed dumbbell-shaped spatial-energy distribution and the influence of beam offset angle provide valuable insights for optimizing X-ray source design and improving radiation protection strategies.