Beam-beam studies for Super Proton-Proton Collider

概要

In China, a two-stage circular collider project, CEPC-SPPC has been proposed. The first stage, CEPC (Circular Electron Positron Collier, a so-called Higgs factory) is focused on the Higgs physics, and the second stage, SPPC (Super Proton-Proton Collider) will be an energy frontier collider and a discovery machine.
Luminosity is a key factor for any particle-physics colliders. With the increasing bunch population, beam-beam interaction is increasingly become the limit factor of luminosity improvement. The finite crossing angle scheme is considered.
Long-range interaction is another significant source of luminosity degrade. In this report, we first don't consider long-range interactions. We study luminosity degrade with crossing angle and without crossing angle for horizontal crossing and horizontal-vertical crossing. Second we discuss luminosity decay with long-range interactions for horizontal crossing and horizontal-vertical crossing. Finally the resulting beam-beam limit will be concluded for SPPC.