Ruling factors in the impact of collision debris on the LHC high luminosity insertion magnets

The Large Hadron Collider (LHC) built at CERN now enters a starting-up phase in order to reach the present design luminosity (L0) of 1034 cm-2·s-1. A possible upgrade of the machine to a luminosity value of 10 L0 requires a new design of some insertion region magnets, and will be implemented in essentially two phases. The energy from collision debris is deposited in the insertion region magnetic elements and in particular in the superconducting magnet coils with a possible risk of quench. The role of the key parameters (such as the magnet aperture, the crossing plane, the thickness of a possible shielding liner, ...) is pointed out, in order to optimize the design of the new insertion regions for the Upgrade phase I aiming to reach 2-3 L0. (author)