MAGNETIC DESIGN OF THE ADVANCED LIGHT-SOURCE ELLIPTIC WIGGLER

An elliptical wiggler has been designed for installation in the Advanc ed Light Source at the Lawrence Berkeley Laboratory. The design has be en optimized for the production of circularly polarized light in the 5 0 eV to 10 KeV energy range. The device will be 3.4 m long consisting of vertical and horizontal periodic structures. The period length for both is 20 cm. The vertical structure is a hybrid permanent magnet des ign which produces a peak field of 2.0 T. The horizontal magnetic stru cture is an iron core electromagnetic design shifted longitudinally by one-quarter period relative to the vertical structure; it has a peak field of 0.095 T. The polarity of the horizontal field can be switched at a rate of up to 1 Hz, which results in a modulation of the chirali ty of the circularly polarized radiation on-axis. This paper discusses the magnetic design and presents the results of radiation spectrum ca lculations used for determining optimal field parameter settings.