Conceptual design of a 16 T cosθ bending dipole for the Future Circular Collider

After LHC is turned off, a new accelerator machine will be needed in order to explore unknown regions of high-energy particle physics. For this reason, the project Future Circular Collider (FCC) has started at CERN, with the target of studying the feasibility of a very large hadron collider with 50-TeV proton beams in a 100-km circumference. The EuroCirCol project is part of the FCC study under European Community leadership. In particular, it has the outcome of producing a conceptual design of the FCC within 2019. One of the main activities is the development of 16-T superconducting dipole able to produce a bore field, in order to bend the beams within energy and size constraints. Here, we present the conceptual design of a Nb3Sn cos theta dipole in double-aperture configuration (LHC-style). We show that it is possible to produce a bore field of 16 T with a good field quality, with reasonable assumptions on the conductor features, and with a reasonable amount of cable. A bladders and keys mechanical structure is also presented, proving that the electromagnetic forces can be maintained, keeping the stress in the coils within a safe limit. Finally, we present a preliminary quench study, showing that the magnet can be protected using well-known technologies.