Field Computations of Sextupole Magnets for Particle Accelerators

Summary from only given, as follows. Sextupole magnets are required in particle accelerators, but their design and computation involve particular difficulties. The characteristic 3-fold rotation symmetry of a sextupole is ill-matched to the 2-fold and 4-fold symmetries often desired for the mechanical location and support of magnets. Also, the quadratic variation of the field within the bore region does not lend itself to computation with first- and second-order finite elements as typically found in computer codes. Computation of sextupole magnets for the Advanced Photon Source (APS) at Argonne National Laboratory (ANL) is described.