SLHCV3.0: layout, optics and long term stability

SLHCV3.0 is a proof-of-principle scenario for upgrading the luminosity of the LHC. It represents an attempt to overcome the limitations of the Phase I upgrade project proposed layout (corre- sponding to SLHCV2.0) and it aims at a substantial luminosity improvement with a minimum set of hardware changes. In this paper we describe the implementation details of SLHCV3.0, the required changes with respect to the nominal LHC, and the expected performance in terms of chromatic aberrations and dynamic aperture.