Sc-47 production from titanium targets using electron linacs

In this work we have studied the feasibility of photonuclear production of 47Sc from 48Ti via 48Ti(γ,p)47Sc reaction. Photon flux distribution for electron beams of different energies incident on tungsten converter was calculated using MCNPX radiation transport code. 47Sc production rate dependence on electron beam energy was found and 47Sc yields were estimated. It was shown that irradiating a natural Ti target results in numerous scandium isotopes which can reduce the specific activity of 47Sc. Irradiating enriched 48Ti targets with a 22 MeV 1 mA beam will result in hundreds of MBq/g activity of 47Sc and no other isotopes of scandium. Decreasing the size of the target will result in much higher average photon flux through the target and tens of GBq/g levels of specific activity of 47Sc. Increasing the beam energy will also result in higher yields, but as soon as the electron energy exceeds the 48Ti(γ,np)46Sc reaction threshold, 46Sc starts being produced and its fraction in total scandium atoms grows as beam energy increases. The results of the simulations were benchmarked by irradiating natural titanium foil with 22 MeV electron beam incident on the tungsten converter. Measured 47Sc activities were found to be in very good agreement with the predictions.