【摘要】 基于Geant4蒙特卡罗程序包建立了低真空条件下高能电子束的输运模型,并用该模型详细研究了电子束在低真空条件的传输特性。结果表明,低真空条件下电子束传输特性与高真空下的有较大差异,环境气体对电子束有散射作用,而磁场可有效约束高能电子的传输轨迹,最终轨迹是磁场约束作用与环境气体散射作用竞争的结果。对于确定的磁场分布,电子束能量存在一个最佳范围,从而保证电子束的传输特性。更多还原

【Abstract】 Based on Geant4 Monte Carlo toolkit,a numerical model is established to simulate the electron beam transportation characteristics under low-vacuum condition.The results indicate that the low-vacuum transportation characteristics differ greatly from the high-vacuum case.The residual gas affects the beam trajectory greatly,but the magnetic field can focus the beam effectively.The final trajectory is determined by both effects.For a given magnetic field,in order to get the desired beam,the beam energy should be in a reasonable range.更多还原