Final design of the cryostat for the high luminosity LHC magnets

Abstract The high luminosity LHC project (HL-LHC) aims at increasing proton collisions by a factor of ten whilst extending physics exploitation until 2035. Its performance will rely on new focusing quadrupoles, beam separation dipoles and corrector magnets with large apertures to be installed both sides the ATLAS CMS experiments. A dedicated cryostat design about 1 m in diameter was developed for operation these 1.9 K, comprising required cryogenic circuits, interconnects, supports, insulation, instrumentation systems. Six cryostats various lengths range 8 11 are each side interaction points house triplet magnets, correctors first dipole. These linked through flexible interconnects form continuous vacuum insulation system 60 length. second rearmost dipole requires stand-alone 15 length but nevertheless features common principles. We present cryostats, from conceptual stage towards final design. Assembly aspects also addressed, including modular approach affording flexibility simplification manufacturing assembly processes.