Development of the superferric sextupole corrector magnet for the LHC luminosity upgrade

The National Institute for Nuclear Physics (INFN) is developing, within the framework of a collaboration agreement with the European Organization for Nuclear Research (CERN), prototypes of five corrector magnets, from skew quadrupoles to dodecapoles, which will equip the high-luminosity interaction regions of the high-luminosity Large Hadron Collider. These magnets are based on a superferric design, which allows a relatively simple, modular, and easy-to-construct magnet. In this paper, we review the main features of the corrector magnets, and we present the results of the manufacture of the sextupole superconducting coils, from the development of suitable solutions for the winding and impregnation to the quality assessment on the series coils, including the results of the first cryogenic tests on a single coil