The SNS Front End Accelerator Systems

The Spallation Neutron Source front end comprises a 35-70 mA volume H source, a multi-element electrostatic LEBT including chopping and steering, a 402.5 MHz RFQ with low output emittance and a 2.5 MeV MEBT also including chopping. The beam duty factor is 6%, with possible extension to 12%. This system, along with an LANL-supplied 1 GeV linac and a BNL-supplied storage ring, provides an average beam power of 1-2 MW to an ORNL and ANLsupplied neutron target and beam instruments facility. The current status of the front end design is described, along with results of several R&D projects leading to the final design.