A neutron production target for FRANZ

A high power target for neutron production has been developed for the upcoming intense neutron source FRANZ at the University of Frankfurt. At this facility neutrons will be produced via the 7Li(p,n)7Be reaction by bombarding layers of a high temperature Li compound with pulsed proton beams of up to 2 mA average current and maximum energies of 2.3 MeV. Cooling is achieved by water flowing under high pressure through capillaries in a 1.2 mm thick copper target. The heat distribution has been calculated with the fluid dynamics code StarCD/3.26, ensuring that the copper surface remains below 500∘C at the maximum beam power of 5 kW. The moderating effect of the cooling water on the neutron spectra was studied by simulations using the GEANT software package. A prototype target was successfully tested at the Karlsruhe Van de Graaff accelerator, confirming stable operation at a thermal load of 5 kW/cm2.