A High Field Superconducting Beam Transport in a BNL Primary Proton Beam

Construction of a slow external beam switchyard at the BNL AGS requires a rapid 20.4° bend in the upstream end of the beam line. Two curved superconducting window dipole magnets, operating at 6.0 T and about 80% of "short sample" magnetic field, will be utilized with two small superconducting sextupoles to provide the necessary deflection for a 28.5 GeV/c primary proton beam. Because the magnets will operate in a primary proton beam environment, they are designed to absorb large amounts of radiation heating from the beam without quenching. The field quality of the superconducting magnets is extremely good. Computer field calculations indicate a field error, ¿B/Bo, equivalent to ± 1 × 10-4 up to 75% of the 8.26 cm full aperture diameter in the magnet.