Interaction Regions for e-p and p-p Collisions in the LEP Tunnel

Studies have shown the feasibility of a p-p collider (LHC) in the LEP tunnel with centre-of-mass energies from 10 to 18 Tev [1] . The proximity of the LEP storage ring [2], with a maximum energy of 100 GeV per beam, offers the possibility of e-p interactions. Because of limitations in space and deflection, it is assumed that e-p insertions are in a straight section between two arcs, which does not contain RF cavities. Among the envisaged insertions, head-on collisions give the highest luminosity. In this case, the electron beam is deflected vertically so that there is a path common to both beams between the LEP insertion quadrupoles used for separating the beams outside this region. In p-p Tode2, this insertion gives a luminosity of 1 to 2×1032cm-2S-1 In e-p mode, the luminosity reaches 1.23×1032 cm-2s-1 for a center of mass energy of 1.5 TeV. The use of collimators reduces the photon background in the experimental region to a tolerable level.