The ring, previously upgraded by PSL in 1975, is a synchrotron light source for research and the calibration of far ultraviolet instruments. It is unique in having a single large magnet for beam confinement, giving a precise uniform beam. PSL designed new steel, new magnetic coils and a field mapper. PSL and SRC jointly designed an upgraded control system that more accurately controls beam parameters. Construction began summer of 1997 and was completed in 1998.
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