Evaluation of the radiation field in the future circular collider detector

The radiation load on a detector at a 100 TeV proton-proton collider, that is being investigated within the future circular collider (FCC) study, is presented. A first concept of the detector has been modeled and relevant fluence and dose distributions have been calculated using the fluka Monte Carlo code. Distributions of fluence rates are discussed separately for charged particles, neutrons and photons. Dose and 1 MeV neutron equivalent fluence, for the accumulated integrated luminosity, are presented. The peak values of these quantities in the different subdetectors are highlighted, in order to define the radiation tolerance requirements for the choice of possible technologies. The effect of the magnetic field is also discussed. Two shielding solutions have been conceived to minimize the backscattering from the forward calorimeters to the muon chambers and the forward tracking stations. The two possible designs are presented and their effectiveness is discussed.