International Linear Collider damping ring lattice design with two wiggler sections

The International Linear Collider (ILC), which is based onsuper-conducting RF acceleration technology, requires the dampingrings to provide beams with extremely small equilibrium emittance,and large acceptance to ensure good injection efficiency forhigh-emittance, and high-energy spread beam from the positron source.In order to reduce the cost for ILC damping rings, an alternativelattice which is different from the baseline configuration design hasbeen designed with modified FODO arc cells, and the total quadrupolenumber has been reduced by half. At the same time, to decrease thetotal cost involved in constructing access shafts needed to supplypower, cryogenics etc. for the wigglers and other systems, the numberof wiggler sections is decreased from 8 to 4, and further to 2. Thisnew lattice has been optimized to have a good dynamic aperture. Thisalternative ILC damping ring lattice design will reduce the costlargely as compared with the baseline design.