Measurement and simulation of the background in the CMS muon detectors

The study of the different backgrounds which the muon detectors of the CMS experiment are exposed to, is fundamental to assess the system longevity and project its performance to the conditions expected for HL-LHC. In this respect, an accurate modelling of the backgrounds in simulation is of prime importance as many studies rely on simulation-based predictions while these future conditions have never been experienced in reality. This paper will present the state of the art of the work carried out to understand backgrounds observed with data collected during the LHC runs, as well as at the CERN high-intensity gamma irradiation facility. Furthermore, the effort made to improve the accuracy of FLUKA and GEANT4 based simulations of background will be thoroughly described.