HE-LHC: The High-Energy Large Hadron Collider: Future Circular Collider Conceptual Design Report Volume 4

In response to the 2013 Update of the European Strategy for Particle Physics (EPPSU), the Future Circular Collider (FCC) study was launched as a world-wide international collaboration hosted by CERN. The FCC study covered an energy-frontier hadron collider (FCC-hh), a highest-luminosity high-energy lepton collider (FCC-ee), the corresponding 100 km tunnel infrastructure, as well as the physics opportunities of these two colliders, and a high-energy LHC, based on FCC-hh technology. This document constitutes the fourth volume of the FCC Conceptual Design Report, devoted to the High-Energy Large Hadron Collider HE-LHC. It summarizes the HE-LHC physics discovery opportunities, presents the HE-LHC accelerator design, performance reach, and operation plan, discusses the underlying technologies, the civil engineering and technical infrastructure, and also sketches a possible implementation. Combining ingredients from the Large Hadron Collider (LHC), the high-luminosity LHC upgrade and adding novel technologies and approaches, the HE-LHC design aims at a hadron collider with about twice the centre-of-mass collision energy that the LHC can reach. Its performance aims at exploring physics beyond the Standard Model, significantly extending the LHC’s direct and indirect sensitivity to new physics and discoveries.