基于14 MeV质子回旋加速器的BNCT中子源实验终端设计  

Experimental terminal design of BNCT neutron source based on 14 MeV proton cyclotron

作　　者：卢宇 李文艺[1] 徐照[1] 李桃生[1,2] LU Yu;LIWenyi;XU Zhao;LI Taosheng(Hefei Institutes of Physical Science,Chinese Academy of Sciences,Hefei 230031,China;University of Science and Technology of China,Hefei 230026,China)

机构地区：[1]中国科学院合肥物质科学研究院,合肥230031 [2]中国科学技术大学,合肥230026

出　　处：《核技术》2022年第3期27-33,共7页Nuclear Techniques

基　　金：中国科学院院长基金(No.YZJJ2020QN31)资助。

摘　　要：随着加速器技术的发展,基于加速器的硼中子俘获治疗装置越来越受到国内外关注。为了研究基于能量为14 MeV、流强为80μA的回旋质子加速器获得硼中子俘获治疗(Boron Neutron Capture Therapy,BNCT)中子源的可能性,利用Geant4软件对中子产生靶以及束流整形组件进行了优化设计,旨在获得理想的超热中子束实验终端。由于加速器的流强较低,增设了天然铀作为中子倍增器以提高中子注量。经过对铍靶、天然铀增殖层、AlF_(3)和TiF_(3)复合慢化体、热中子吸收层和γ屏蔽层等进行优化设计,在束流出口处能够获得超热中子占比高达95.6%,注量率可达6.26×10^(7) n·cm^(−2)·s^(−1)的中子源终端。该方案可初步用于加速器BNCT中子源实验终端的技术验证。[Background]With the development of accelerator technology,the accelerator-based Boron Neutron Capture Therapy(BNCT)has attracted more and more attention,and metallic ^(9)Be is one of the most suitable materials for neutron-producing targets.[Purpose]The study aims to investigate the possibility of obtaining BNCT neutron sources based on proton cyclotron with energy of 14 MeV and current intensity of 80μA.[Methods]Geant4 was used to simulate the neutron beam properties of Be target bombarded by 14 MeV proton beams and to optimize the target thickness.In addition,spherical natural uranium was considered as a neutron multiplier,the neutron beams generated by the combination of different materials and thicknesses of Beam Shaping Assembly(BSA)were investigated by simulation.[Results]The optimized irradiated field at beam outlet of proton cyclotron can reach 95.6%of epithermal neutrons,and 6.26×10^(7) n·cm^(−2)·s^(−1) of the epithermal flux rate.[Conclusions]This design solution can be initially used for the technical verification of BNCT neutron source experimental terminal.

关 键 词：硼中子俘获治疗 GEANT4 ^(9)Be(p n)反应 束流整形组件 超热中子场 

分 类 号：TL99[核科学技术—核技术及应用]