Influence of the electron beams incidence angles on the depth-dose distribution of the irradiated object

Highlights: • The possibility of improving the method of depth-dose uniformity has been investigated. • The optimal irradiation parameters were determined for high efficiency of the electron beam. • A significant decrease of the depth-dose inhomogeneity under double-side irradiation was achieved. To improve the efficiency of radiation polymerization, crosslinking, etc. A method was proposed for a significant decrease in the depth-dose inhomogeneity in a layer under double-sided irradiation by two electron beams: the main beam incident perpendicular to the surface (Θ = 0°) and the additional beam Θ ≠ 0°. To study the possibilities of the proposed method, the deposit depth-doses in the irradiated polyethylene layer were simulated by the Monte Carlo method. The optimal thicknesses of polyethylene layers and the ratio of the intensities of the main and additional beams for different incidence angles Θ of electrons with the energies of 2, 6, 10 MeV were determined. It was shown that the additional use of thin aluminum filters under two-sided irradiation by two beams with optimal parameters reduced the depth-dose inhomogeneity to ≈5 ÷ 6%. In this case, the efficiency of using the energy of the electron beam is ≈ 93%. The influence of the energy spread of the electron beam on the magnitude of the depth-dose inhomogeneity and methods for reducing this influence was discussed.