Generation of various polarization states from insertion devices: A review

Abstract

Most insertion devices (IDs) which have been built so far are planar with the field in the vertical plane. They are the easiest to design, and they fit well to the narrow vertical aperture available on storage rings. As bending magnets, these IDs generate essentially horizontally polarized radiation. Recently, several new proposals and prototypes have been produced in order to generate different polarization states. The Stokes decomposition of the radiation from these devices is given versus photo energy. This discussion is illustrated by taking the European Synchrotron Radiation Facility (ESRF) conditions in the hard x-ray range.