Beam dump optics for the spallation neutron source

The Spallation Neutron Source accelerator complex will have three beam dumps for beam tuning and for the collection of controlled losses. The linac and extraction beam dumps will be used for beam tuning purposes and are designed for 7.5 kW of beam power. The optics issues for these dumps are i) the beam size at the vacuum window which is near the last quadrupole and ii) guaranteeing the beam size at the dump due to multiple scattering in the presence of potentially large variations in the linac and accumulator ring emittances. The injection dump will collect the partially stripped H⁰ ions as well as H^- ions which have miss the foil and is designed to absorb up to 200 kW of beam power. The closed orbit for these ions are much different in the injection area and have to be collected in the injection beam dump with a certain beam size