Status of the Large Hadron Collider magnet development

Abstract

CERN is preparing the construction of a new particle accelerator-collider the Large Hadron Collider (LHC), which will be installed in the existing 27 km tunnel of the Large Electron-Positron Collider (LEP). The LHC will require in total about 10,000 superconducting magnetic units, including main magnets and correction elements. For the regular arcs of the machine 1300, 13.5 m long dipole magnets of 8.65T and 600, 3.2 m long quadrupoles of 220 T/m gradient will be used. These main magnets will all be of the twin-aperture configuration, i.e. with the magnetic channels for the two beams placed in a common yoke and cryostat. R&D for the LHC high field magnets is now approaching its goals. The last short dipole model reached the record field of 10.51 T and after thermal cycling had all quenches well above the LHC required field. A 10 m long prototype confirmed the validity of two major technical choices by behaving perfectly in superfluid helium and showing no adverse effects of the twin-aperture configuration. Fabrication in industry of seven full size dipoles is well advanced and two prototype quadrupoles are completed and ready for testing.<<ETX>>