Undulator engineering for synchrotron radiation applications

Six undulators have been designed and built by STI since 1980 for synchrotron and FEL applications. Several design concepts, producing successively higher fields, have been developed during this period. A wedged‐pole hybrid design has been demonstrated to yield the highest field to date for a given gap‐to‐wavelength ratio. A simple method of reducing field errors has been demonstrated on the wedged‐pole hybrid, and it may lead to significant cost reduction through relaxation of mechanical and magnet tolerances.