Beam-beam issues for LHC upgrade phases 1 and 2

While long-range beam-beam interaction will not be the limiting effect in the first years after LHC start-up, it will definitely become one in the upgrade scenarios. Upgrade phase 1 will include an exchange of the triplet magnets allowing for a = 25 cm optics. Phase 2 is an even more ambitious upgrade that will include a modification of the detectors. Currently two phase-2 upgrade scenarios are proposed: the “Dipole Zero” (D0) and the “Large Piwinski Angle” (LPA) option. After some general notes and a brief description of the applied simulation model, the upgrade phase 1 issues and optics will be discussed with regard to beam-beam performance. The following two sections will deal with upgrade phase 2.