Design and fabrication of the prototype superconducting tuning quadrupole and octupole correction winding for the LHC project

CERN is preparing for the construction of the Large Hadron Collider (LHC) to be installed in the Large Electron Positron Collider (LEP) tunnel. The magnetic lattice of the LHC will consist of a ring of twin-aperture dipoles and quadrupoles, connected electrically in series. To adjust the working point of the machine, tuning quadrupoles will be installed in pairs in each regular cell, next to the main quadrupoles. Also, to correct multipolar field errors in the LHC, an octupole correction winding is required near each lattice quadrupole. A nested construction of these two magnets is foreseen. The design of a prototype tuning quadrupole and octupole corrector is described. Details of magnetic and mechanical calculations are given, including results from existing and specially developed computer codes, and model work. Further, the construction procedures are described, including the facilities and tooling developed by ACICA for this work. >