Results of the radiation dose study around the tested gem muon detector at cms

The higher luminosity delivered by the future HL-LHC imposed the development and testing of a new type high-rate detector known as GEM (Gas Electron Multiplier). A monitoring system, designed to measure the radiation dose and particle fluence around the GEM detectors, has been developed and installed at the CMS detector. It consists of a main controller, to which up to 12 radiation monitors (RADMON) can be connected. There are two types of sensors in each unit: RadFETs, measuring the total radiations dose and p-i-n diodes for 1 MeV neq fluence. A few GEM chambers were installed in the inner CMS endcap in early 2017 for a slice test. One RADMON is installed in one of the chambers to measure the surrounding radiation. After about two years of operation, the obtained results are analyzed. They show that for an integrated luminosity of about 118 fm -1 the dose and the 1 MeV fluence are relatively low. Therefore, only two more sensitive sensors are giving data. The experimental results confirm the dose and fluence values simulated by FLUKA v.3.0.0.0.