Perspectives on variable‐period/polarizing insertion devices in synchrotron radiation science and technology: Recent developments at SSRL (abstract)

Abstract

Insertion devices that are tuned by electrical period variation, in contrast to the conventional method of mechanically varying the field strength, offer a number of advantages for the successful development of the next generation of higher‐brightness storage rings and associated experimental techniques [R. Tatchyn, Nucl. Instrum. Methods A 275, 430 (1989); J. Appl. Phys. 65, 4107 (1989); R. Tatchyn and T. Cremer, IEEE Trans. Mag. 26, 3102 (1990)]. for example, due to the inherently low total output power levels of variable‐period devices, their use can do more to relax power loading constraints on beamline optics at existing and future facilities than many of the alternative approaches explored in recent years, such as, e.g., gallium‐cooled optics, multilayer premonochromator structures, or adaptive/deformable optics. With regard to machine optics, variable‐period structures can be operated without varying the tune of the host machine lattice, enabling the design and flexible operation of ultralarge, yet...