Yield decline of sweet potato in the humid lowlands of Papua New Guinea

A study of the properties of the neutron production target for the China accelerator-driven system induced from 150-MeV incident proton energy and a 3-mA beam current is performed. The selection of the material and geometry design for the target; the physics properties of the target involved in this work including the neutron yield, energy, and space distribution for the neutrons leaked from the target; and the spallation fragment of charge and mass distribution have been investigated using the SHIELD code. An analysis of the target radiation damage and energy deposit is also carried out.