Chapter 9: Cryogenics for the HL-LHC

The upgrade of the cryogenics for the HL-LHC will consist of the following: - The design and installation of two new cryogenic plants at P1 and P5 for high luminosity insertions. This upgrade will be based on a new sectorization scheme aimed at separating the cooling of the magnets in these insertion regions from the arc magnets and considering the newt feedboxes and superconducting links located in underground infrastructures. - The design and installation of a new cryogenic distribution lines (QXL) at P1 and P5 in the LHC tunnel and in a new underground service galleries. - The upgrade of the existing cryogenic plant (QSRA and QURA) cooling the LHC sector 3-4 located at P4. - The cryogenic design support for superconducting devices, such as magnets, crab cavities, superconducting links, and the hollow electron lenses. Some other options such as new cryogenic circuits at P7 for the HTS links and displaced current feedboxes or a new cryoplant in P4 have been discarded.