DC septum magnets and their leakage field effects on an electron beam in the SPring-8 storage ring

We fabricated improved DC septum magnets that have smaller leakage fields for continuous beam injection. We changed the shape of the coil and placed field clamps at both ends of the magnets. We increased the thickness of the septum-plane shields and extended them to the field clamps. Leakage fields were measured and the effect they had on an electron beam during injection was studied. After reducing the leakage fields, the orbit changes during injection were less than the beam sizes, which satisfied the requirements for continuous beam injection.