Design of a high-field twin aperture superconducting dipole model

An initial design for the Large Hadron Collider to be installed in the tunnel of the CERN LEP machine is based on the so-called two-in-one concept, originally proposed and tested at Brookhaven National Laboratory for fields up to approximately 5 T. The dipole magnets of the two rings have a common magnetic circuit and are located in one cryostat. Two major lines of development are followed for the construction of models of high-field magnets: (1) using Nb₃Sn superconducting cables at 4.5 K, and (2) using NbTi alloy superconducting cables at 2 K. The models discussed are 1 m long twin aperture dipoles. They employ NbTi alloy superconducting cables at 2 K but, apart from the coils, the mechanical design concepts are equally valid for magnets using using Nb₃Sn cables. A role of the models is to test the various components and procedures of fabrication in order to obtain the best performances at lowest cost. Possible variants in the design are mentioned.