Monte Carlo simulation of the CERN-EU High Energy Reference Field (CERF) facility

In the present paper Geant4 Monte Carlo simulations of the CERN-EU high-energy Reference Field (CERF) facility in Geneva, Switzerland, are presented. At this facility a neutron field with a broad energy distribution from thermal energies up to GeV is available. To validate the simulated neutron fluences, the CERF neutron energy distribution was also measured with an extended range Bonner Sphere Spectrometer. Both measurements and simulations are compared against the official CERF reference distributions that were calculated with the Monte Carlo code FLUKA. It turned out that the differences between the total neutron fluences simulated with Geant4 and those measured were less than 41%, depending on the measurement position. While the total fluences simulated with the Geant4 Binary INC model (QGSP_BIC_HP) and the corresponding FLUKA reference values were up to 41% lower than those measured, the total fluences simulated with the Geant4 Bertini INC model (QGSP_BERT_HP) overestimated (up to 27%) the experimental results. As compared to the measured ambient dose equivalent H*(10), similar differences were observed with H*(10) values higher by about 29% for the Geant4 Bertini INC simulations and lower by about 48% for the Geant4 Binary INC and FLUKA simulations. •Monte Carlo simulation of the CERF facility.•Geant4 Simulation using two different high energy models.•Neutron spectrometry with an Extended Range Bonner Sphere Spectrometer.•Comparison with FLUKA Monte Carlo calculations.