Phase 1 Optics: Merits and Challenges

Low gradient optics have been proposed for an upgrade of the LHC interaction region. Using lower gradient, larger aperture and longer NbTi quadrupoles with respect to the nominal layout, it is possible to achieve = 25 cm with additional aperture margins and better dynamic aperture. The main drawbacks are an increase of the number of the long range interactions and limitations in the downstream matching section. Four layouts and optics, which span the parameter space and modularity for NbTi technology, are proposed and studied extensively in order identify and quantify the merits and challenges.