Herman M W, Dockter A E, Scallon J E
Med Phys. 1980 Jan-Feb;7(1):70-2. doi: 10.1118/1.594768.
Siemens Corporation defines the source of the Mevatron 20 linear accelerator as a line source approximately 2 m in length. Calculations for secondary barriers for leakage radiation are generally based on 0.1% of the useful beam 1 m from the target. The difference in source terms can lead to calculating thinner barriers than are required. The placement of a 30 X 10 X 10-cm block of lead behind the head was required to achieve acceptable radiation levels.
西门子公司将Mevatron 20直线加速器的源定义为一个长度约为2米的线源。泄漏辐射次级防护屏蔽的计算通常基于距靶1米处有用射束的0.1%。源项的差异可能导致计算出的防护屏蔽比实际所需的更薄。需要在机头后面放置一块30×10×10厘米的铅块，以达到可接受的辐射水平。
