Experiments requirements and limitations for post LS1 operation

The LHC will resume operation for physics in 2015, after a two year long shutdown, with an energy target of 13 TeV and a peak luminosity target of ~10 34 cm-2 s-1. The physics goals will be rich, with difficult precision measurements of the properties of the newly found Higgs boson, as well as of other equally important phenomena predicted by the standard model. With the higher energy, the experiment communities will also be looking for physics beyond the standard model. The two programs, which sometimes have diverging demands on the accelerator, need to be reconciled to guarantee the highest scientific output of the LHC. In this talk, we review the running scenarios for the Proton-Proton and Heavy Ion collider runs after LS1, in particular with respect to the issues related to bunch spacing (pileup , triggers and reconstruction efficiency), but also to other aspects like bunch length, filling schemes, leveling, etc., as well as the experimental and technical challenges in the different scenarios.