LHC Normal Conducting Magnets Toward HL-LHC and Beyond: Life Span Evaluations, Corrective Actions, and Future Upgrades

After an overview of the radiation hardness needs for the normal conducting magnets installed in the present Large Hadron Collider (LHC) and for the future high-luminosity LHC (HL-LHC) exploitation, this paper describes the tests and modifications that have been carried out on the presently installed magnet types to evaluate their reliability and enhance their lifespan. In spite of the ongoing optimization, it has become evident that to comply with the HL-LHC requirement, new radiation hard magnets will be necessary for the most exposed locations: The solutions under study and the possible approaches will be discussed.