The ESS Linac Design

The European Spallation Source (ESS) is a 5 MW, 2.5 MeV long pulse proton machine. It represents a big jump in power compare to the existing spallation facilities. The design phase is well under way, with the delivery of a Conceptual Design Report published in the beginning of 2012, and a Technical Design Report in December 2012. Why and how the 5 MW goal influences the parameter choices will be described.