Linear optics and coupling correction of ILSF storage ring lattice

The Iranian Light Source Facility (ILSF) is a 3 GeV synchrotron radiation facility, which is in the design stage. The ILSF storage ring design is based on a five-bend achromat lattice providing an ultralow horizontal beam emittance of 0.27 nm-rad. Inevitable errors like imperfection of magnetic field and misalignment of magnets will introduce various destructive effects on the performance of the machine. The possibility of correcting the errors should be thoroughly examined before settling the design. In this paper, we have tried to estimate the errors as realistic as possible based on the results obtained from the simulation of the elements and the accuracy of the predicted equipment for fabrication and alignment. The influence of errors on the lattice is investigated. Closed orbit distortion, beta beating and betatron coupling are corrected and improvement made in the lattice functions and machine performance will be presented.