An Early-days Configuration to be used when commissioning the machine. The Nominal Configuration for ion collisions . We discuss under the various configurations the corresponding requirements and their optical implementation. The tuning of the insertions at injection, including the choice of the separation plane, is dictated by the contradicting requirements of separating the two beams by at least 10 sigmas and of avoiding any mechanical aperture limitation close to the delicate physics detectors. Special provisions are taken to avoid beam losses even in the event of a failure of the injection system.
More information is available in the discussion of the optics for injection .
This configuration is consistent with the official parameter list of the LHC project. The other two experimental insertions are left at their injection tuning and the beams remain separated there. Long Range B-B Tune Spread . . It is highly probable that the four LHC experiments will define a mode of operation where all detectors are active. This is the purpose of the Operational Configuration.