Measurement of Differential Thick-Target Neutron Yields of C, Al, Ta, W(p,xn) Reactions for 50-MeV Protons

Energy-angular differential thick-target neutron yields were measured at 50 MeV for the C, Al, Ta, W(p,n) reactions with a time-of-flight (TOF) method using the Tohoku University K = 110-MeV cyclotron equipped with a beam-swinger system and a well-collimated TOF line. Neutron spectrum data have been obtained down to ~0.8 MeV from the highest energy by use of two different experimental setups to extend the dynamic range of the energy range. Data were obtained at six laboratory angles from 0 to 90 deg. The results are compared with the recent data library LA150. LA150 reproduces the general trend of the experimental data fairly well but still shows marked systematic disagreement in particular in high-energy regions.