HL-LHC IT STRING: Status and Perspectives

The HL-LHC IT STRING, an integrated test stand for the major components of the HL-LHC Inner Triplet (IT) zone, is in its construction phase in a surface building at CERN. The main motivation is to study and validate the collective behavior of the different systems: magnets, circuit protection, cryogenics for magnets and superconducting link, magnet powering, vacuum, alignment, and interconnections between magnets and superconducting link. During the past two years, the major focus has been on the technical infrastructure definition and implementation, while preparing the installation sequences and procedures for the major elements. The String Validation Program (SVP) has been agreed with the HL-LHC Work Packages, allowing to set up a joint and optimized test program and to integrate it in a schedule. In this paper we describe the IT String installations and describe the main differences between the HL-LHC IT String and the future HL-LHC machine. The main line of the test program and the motivation of a full thermal cycle with a cost benefit analysis will be presented.