Study on the edge-cooling target structure for transportable accelerator-driven neutron source

As the Transportable Accelerator-driven Neutron Source (TANS) for the non-destructive testing of outdoor infrastructure requires efficient neutron production with low power, we studied the target structure design based on the 7Li (p, n) 7Be reaction under a 2.5 MeV proton beam injection. For practical applications of TANS, the neutron attenuation in the forward direction should be as low as possible, thus we decided to investigate water-cooling target structures, including an edge-cooling type. Relevant parametric simulations of the material thickness of target structures and water flow rates were carried out in both edge-cooling and conventional back-cooling types. The comparison of neutron attenuation and cooling capability shows that the edge-cooling target has a good performance not only in keeping the temperature within a reasonable range but also in providing the necessary intensity of forward-emitting neutrons with less attenuation, which is suitable for practical applications of TANS. And the stress analysis proves the engineering feasibility of edge-cooling target in operation. In addition, the induced radioactivities and associated dose rates were estimated for the edge-cooling structure model.