Test of a high-field bend magnet for the ALS

It is possible to replace several of the existing 36 conventional 1.5 T, 1 m long bend magnets in the ALS (Advanced Light Source) at LBNL with short, higher field superconducting magnets to produce synchrotron radiation with higher energy. The authors have built and tested four prototype magnets using different conductors, coil shapes, structural support and fabrication methods. All reached the required field for bending 1.9 GeV electrons 10 degrees; however, the first three had excessive training. The final design, Superbend 4, reached short-sample current with no training. Construction details, stress analysis and test results are presented for Superbend 4.