Beam instrumentation for the Spallation Neutron Source ring

The Spallation Neutron Source (SNS) will be constructed by a multi-laboratory collaboration with BNL responsible for the transfer lines and ring. The 1 MW beam power necessitates careful monitoring to minimize un-controlled loss. This high beam power will influence the design of the monitors in the high energy beam transport line (HEBT) from linac to ring, in the ring, and in the ring-to-target transfer line (RTBT). The ring instrumentation must cover a 3-decade range of beam intensity during accumulation. Beam loss monitoring will be especially critical since uncontrolled beam loss must be kept below 10^-4. A Beam-In-Gap (BIG) monitor is being designed to assure the out-of-bucket beam will not be lost in the ring