The use of gradient sector magnets in Chasman-Green lattice (abstract)

The design of the next generation synchrotron radiation ring is based on a low-emittance storage ring with large numbers of zero-dispersion straight-section for insertion devices. As a candidate, the Chasman-Green lattice is likely to be the most promising to be investigated. In this paper, field gradients and edges which are not perpendicular to the optic axis are proposed to introduce the bending magnets for a low-emittance Chasman-Green lattice. The horizontal beam emittance of a large ring is generally expressed as1 (1) εx=Cqγθ3F(ψ)/Jx, where Cq=3.83x10-13 m, γ=Lorentz factor of the stored beam, θ=bending angle of a dipole magnet, F(ψ)=emittance form factor as a function of the betatron phase advance per half cell ψ, Jx=partition number of the horizontal betatron oscillation