Presentation by Wolfgang Hees at Jefferson Lab on 2011-10-06:
The European Spallation Source (ESS) has the mandate to design, build and operate the worlds most powerful neutron source. In 2010 the Accelerator Design Update collaboration was formed to update the 2003 design, and to deliver a Technical Design Report at the end of 2012. Detailed planning for the Prepare-to-Build prototyping project has begun, and potential future power upgrades are being considered. First protons are expected in 2018, and first neutrons in 2019.
The linac will deliver 5 MW of 2.5 GeV protons to a single target, in 2.86 ms long pulses with a 14 Hz repetition rate. It will have a normal conducting front end with an ion source, a Radio Frequency Quadrupole, and a Drift Tube Linac. The superconducting part of the linac contains spoke cavities followed by two families of elliptical cavities.
One of the main challenges for the linac is the tight schedule for design, prototyping, testing, manufacturing and installation of the cryomodules. Another challenge is our ambition to be the world's first sustainable research lab, putting severe limits on energy consumption and therefore on the cryo system's heat load. A hybrid cryomodule concept is being developed in order to combine the low heat load on a continuous cryostat with the flexibility of a segmented design.