Electromagnetic wiggler technology development at the Lawrence Livermore National Laboratory

As a part of the program in induction-linac free-electron laser research, the authors summarize the Laboratory´s work in a variety of activities addressing the requirements imposed on wiggler systems. The development of improved designs is reported for DC iron-core electromagnetic wigglers to attain higher peak fields, greater tunability, and lower random-error levels. Specialized control systems are noted (such as magnetic-field and beam-position controllers) that can relax requirements on the wiggler itself. Basic studies to establish the effect of radiation on permanent magnets are also discussed briefly.