Space charge and coherent effects in the NSNS storage ring

The goal of the proposed National Spallation Neutron Source (NSNS) is to provide a short pulse proton beam of about 0.5 {mu}s with average beam power of 1-2 MW. To achieve such a purpose, a proton storage ring operate at 60 Hz with 1-2 x 10 {sup 14} protons per pulse at 1 GeV is required. The proton storage ring is one of the major systems in the design of the NSNS. The function of the storage ring is to take the 1.0 GeV proton beam from the Linac and convert the long Linac beam of about 1 ms into a 0.5 {mu}s beam in about one thousand turns. The final beam has 1 x 10 {sup 14} proton per pulse, resulting in 1 MW average beam power at 60 Hz repetition rate. Provision has been reserved for a future upgrade to 2 MW by doubling the storage beam to 2 x 10{sup 14} proton per pulse. The lattice of the storage ring is a simple FODO lattice with three-fold symmetry and the dispersion function is reduced to zero at straight sections by the missing magnet scheme. The total circumference of the ring is 208.6 m and the transition energy is 3.43, higher than the operating energy of 1 GeV to avoid the difficult instability problem that are expected above transition. Other salient design parameters are shown in Table 1