Optimal design and field measurements of a dipole magnet model for compact electron storage ring [LSI production]

Compact electron storage rings with strongly curved superconducting dipole magnets were developed as the soft X-ray source for the production of LSI (large scale integration). A dipole magnet model with a copper quasi-cosθ winding was manufactured, and the field distributions were measured. An optimal design technique based on the linear programming and two-dimensional field calculations by the finite element method was applied to determine a coil configuration in a 180° sectoral dipole magnet model. Using this model, good agreement between the measured and calculated field uniformities within the order of 10^-4 was obtained. Moreover, a designed good field region of about 50 mm wide was achieved. This result shows the validity of the design techniques