Design of a damping ring for the SB-Linear-Collider project at DESY

For the SB-Linear-Collider project (SBLC) at DESY a redesign of the damping ring has been performed, mainly in order to optimise the dynamic aperture. The lattice of the proposed damping ring has a DBA structure, similar to the 3rd generation light sources ESRF, APS and SPRING-8. The damping ring is build up with 6 superperiods. The straight sections between these periods are used for the injection, ejection and rf-cavities. In turn, each superperiod consists of 6 DBA cells. The straight sections of these cells are used for the installation of the wigglers, which are needed for the damping. With the installation of overall 150 m of wigglers (B₀=2 T and λ₀=0.2 m) the equilibrium emittances are ε_x,0=6.5.10^-10 m.rad and ε_y,0=1.3.10^-11 m.rad the corresponding normalised emittances are: ε_x,n=3.8.10^-6 m.rad and ε_y,0=7.6.10^-8 m.rad. The damping time results in τ_y⩽3.4 ms. The dynamic acceptance including misalignment and magnet errors is in the range of A_x⩽72 mm.mrad and A_y⩽80 mm.mrad