The FCC-ee detector and physics studies are carried out in the framework of the FCC collaboration, currently comprising ~90 institutes.
The FCC-ee accelerator study foresees electron-positron collisions at ~350 GeV (top quark pair production threshold), 240 GeV (maximum of Higgs boson production through Higgsstrahlung), 161 GeV (pair production of W bosons) and 91 GeV (Z boson production peak). The luminosity of FCC-ee increases with decreasing centre-of-mass energy, with luminosities that are significantly higher than LEP at the Z peak and WW pair production maximum. This allows for high-statistics measurements of electroweak observables. Experimental conditions at FCC-ee are characterised by high bunch crossing rates, especially at 91 GeV, and impact from synchrotron radiation, in particular at 350 GeV. The detector design is currently being adapted to these conditions.
Two detector concepts are under study for FCC-ee. One concept is an adaptation of the CLIC detector concept for FCC-ee. It foresees silicon-based tracking and fine-grained calorimetry. The other concept foresees a large gaseous tracker and dual readout calorimetry. In both cases the detectors are placed in a superconducting solenoid with a 2 Tesla field.