Radiation-hard, pulsed magnets for the CERN ACOL injection line

As part of the upgrading of the CERN Antiproton Collector source facility, the target station and injection line are being rebuilt. The beam transport magnets immediately downstream of the target are expected to receive a lifetime radiation dose in the range 10⁸ to 10⁹ Gy. A description is given of these magnets, two quadrupoles and two dipoles which are made entirely of inorganic materials. They are to be powered by existing pulse power supplies which have 25-kJ capacitor banks operating at 4 kV. In the quadrupole magnets, each pole has eight turns insulated by air and supported by ceramic pieces. The peak current is 4 kA. For the dipole magnets, it was decided to use a single turn carrying a peak current of 70 kA together with a 18:1 turns-ratio matching transformer. The coil insulation is a combination of air and pieces made from a hydrated calcium aluminate cement.