Photoneutronic aspects of the molybdenum-99 production by means of electron linear accelerators

Monte Carlo simulations were used to study Mo-99 photonuclear production. Simulation showed that direct production of Mo-99 in the cylindrical Mo-100 target provides higher values of Mo-99 specific activity compared to production using separate bremsstrahlung converter. For 50 MeV 100 kW electron beam we obtained the maximum value of 61 Ci/g specific activity of produced Mo-99 at saturation. Calculations for the targets with optimized shape showed that even higher levels of specific activity are achievable: for optimized target the calculated value of Mo-99 specific activity at saturation exceeds values of 145.89 Ci/g for setup with bremsstrahlung converter and 170.07 Ci/g without the converter.