An alternative lattice design for ILC damping ring

The ILC damping rings should provide beams with very low natural emittances for the linear collider to reach the required luminosity, and at the same time, the damping rings also need to have a large acceptance to ensure good injection efficiency for high emittance, high energy spread beam from the positron source. Meeting the above requirements is a real challenge for the ILC damping ring lattice design. In order to reduce the cost for ILC damping rings, an alternative lattice different from the baseline configuration design has been done with modified FODO cells, and the total quadrupole number has been reduced by half. The new lattice has been optimised to have good dynamic apertures.