摘要

The luminosity upgrade of the LHC requires replacing the magnets around the ATLAS and CMS experiments with larger aperture dipoles, quadrupoles and correctors. The goal is to have a magnetic lattice that can allow to halve the beam size in the collision points with respect to present baseline. Within the framework of HiLumi LHC, CEA-Saclay studied the replacement of the 70-mm double aperture quadrupole Q4, with a 90-mm magnet based on Nb-Ti technology. The main challenges are due to the distance between the beams of 194 mm, giving a non-negligible magnetic coupling between the two apertures. The coil chosen to be the baseline is a single layer with 15-mm-width cable of the LHC MQ quadrupole. The mechanical structure is based on stainless steel collars to withstand the Lorentz forces. The iron yoke has a magnetic function, and guarantees the alignment of the two apertures. Electromagnetic and mechanical aspects and effects of unbalanced regimes on the field quality have been analyzed. A 3-D design of the coil ends is obtained by minimizing both the integrated multipoles and the peak field.

  • 出版日期2015-6
  • 单位中国地震局