High-power Lithium Target for Accelerator-based Bnct

A water-cooled conical target for producing neutrons via the Li(p,n)Be reaction at 2.5 MeV is under development at Linac Systems. The target is intended to accept an expanded 50-kW beam from an rf linac, and is predicted to meet the intensity requirements for practical accelerator-based boron neutron capture therapy (BNCT) in concert with Linac Systems’ CW RFI linac[1]. Lithium metal targets present well-known physical and mechanical challenges at high beam power density that are addressed in our design. CFD modelling indicates that the peak lithium temperature can be held below 150°C with a water flow rate near 80 kg min and corresponding pressure drop of 170 kPa. The target prototype has been fabricated and is undergoing thermalhydraulic testing using an electron beam at the Plasma Materials Test Facility, Sandia National Laboratories.