Operation of synchrotron light sources with multiple insertion devices

The stability requirements of the next generation of synchrotron radiation facilities have been achieved on insertion device (ID) beamlines of existing rings. However, one ID affects the stored beam and hence the performance of all the other beamlines. Since the effects of the undulators are cumulative, higher levels of performance are required of the accelerator in order to meet and exceed present day standards in rings with many undulators. The authors report experience to date in the areas mentioned above at several multiundulator facilities and efforts to address these problems at facilities in the planning and construction phase. They treat orbit control and feedback. Work on linear and nonlinear effects of ideal undulators in accelerators is described. Undulator imperfections and the demands they make on the accelerator control system are also discussed.<>