论文部分内容阅读
设计了一个用于D-T快中子治疗的准直屏蔽体,通过D-T中子在准直屏蔽体中的MCNP模拟,计算了屏蔽体外透射中子和透射光子在水中的吸收剂量,由此评价了准直屏蔽体的屏蔽效果。利用MCNP程序,模拟了准直中子束及中子束中的γ射线在源皮距(SSD)100cm处的能谱,计算了γ射线与中子束在水中吸收剂量的比值,对准直中子束中γ射线的污染水平进行了评价。完成了准直中子束在人体组织等效水箱中输运的MCNP模拟,给出了吸收剂量深度分布、吸收剂量横向分布和吸收剂量等剂量曲线。
A collimating shield for DT neutron therapy was designed. By using MCNP simulation of DT neutron in collimating shield, the absorbed doses of transmitted and transmitted photons in water were calculated. Collision shield shielding effect. Using the MCNP program, the energy spectra of collimated neutron beam and neutron beam at source pitch (SSD) of 100 cm were simulated. The ratio of γ-ray to neutron beam absorbed dose in water was calculated. The level of gamma ray contamination in neutron beams was evaluated. The MCNP simulation of collimated neutron beam transport in human tissue equivalent water tank was completed. The dose distribution curve of absorbed dose, horizontal distribution of absorbed dose and absorbed dose were given.