【摘要】 在建的大连自由电子激光(Dalian Coherent Light Source,DCLS)是我国第一个开工建设的四代光源,也将是全球唯一可调波极紫外自由电子激光器。本文采用蒙特卡罗程序FLUKA,建立了电子束流线源均匀模型(均匀电子固定角度发射),对DCLS注入器段的主体墙厚度做了屏蔽设计,计算中引入方差减小技巧,以降低计算结果的统计误差;并将基于束流线源模型的蒙特卡罗计算结果与基于经验公式的Shiled11软件的计算结果做了比较。结果表明,基于束流线源模型的蒙特卡罗计算结果与基于经验公式的Shiled11软件的计算结果吻合较好;主体墙外的剂量主要是由中子贡献,95%以上的中子剂量是由巨共振中子贡献。因此,基于电子束流线源模型的蒙特卡罗方法适用于电子直线加速器的主体墙的横向屏蔽设计。更多还原

【Abstract】 Background:Dalian Coherent Light Source(DCLS) which is under construction is the first fourth-generation light source in China,and the only free electron laser with adjustable ultraviolet waves in the world.Purpose and Methods:By adopting the FLUKA code,a cylinder-tunnel geometric model and a line-source sampling physical model are constructed to calculate the thickness of shielding walls in the section of injector.The difference is discussed by comprehensive comparison of calculation results based on FLUKA and SHIELD11.Results:The results based on the FLUKA coincide with that based on SHILED11.The dose out of shielding walls is mainly comprised by the dose of neutron,and the dose of Giant-Resonance accounts for more than 95% of neutron dose.Conclusion:Line-source sampling physical model constructed based on Monte Carlo method can be used in shielding design of electron accelerator’s main walls.更多还原