Triple-GEM detectors were selected by the CMS Collaboration for instrumenting the high η region of the muon system. This region is characterized by a huge radiation background, mainly composed by ...neutrons and photons. In this context, a discharge probability test was performed in 2017 at the CHARM facility at CERN, to study the operation of the detector in an environment similar to the one of the CMS muon system. A Geant4 simulation was developed in parallel to the actual test, in order to evaluate the behaviour of the detector. This paper will present this simulation, from the detector geometry implementation to the results obtained in terms of sensitivity and energy deposited into the gas gaps.
We present the status of the commissioning and integration of the GE1/1 slice test detectors into CMS. Ten Triple-GEM detectors were installed at the beginning of 2017 in CMS to obtain installation ...and commissioning expertise, as well as to demonstrate the integration into the CMS system. The paper will enlight the configuration of the slice test and then focus mainly on the integration activities and status.
•Ten Triple-GEM detectors were installed in the CMS muon system in January 2017.•The aim of the slice test is to prove the integration of the new system into CMS.•The GEM Detector Control system is integrated since December 2017.•The first global runs including also GEM were taken at the beginning of 2018 run.
The CMS Collaboration is developing GEM detectors for the upgrade of the CMS muon system. Their performance will be presented, analyzing the results of several test beams and an irradiation test ...performed in the last years.
•Gas Electron Multiplier for the upgrade of the CMS muon system will be discussed.•Performance obtained at test beams at CERN and Fermilab will be presented.•GEM technology is capable of sustaining the environment of HL-LHC.
The CMS Collaborationhas been developing large-area Triple-GEM detectors to be installed in the muon endcap regions of the CMS experiment in 2019 to maintain forward muon trigger and tracking ...performance at the HLLHC. Ten pre-production detectors were built at CERN to commission the first assembly line and the quality controls. These were installed in the CMS detector in early 2017 and are currently participating in the 2017 LHC run. The collaboration has prepared several additional assembly and quality control lines for distributed mass production of 160 GEM detectors at various sites worldwide. During 2017, these additional production sites have been optimizing construction techniques and quality control procedures and validating them against common specifications by constructing additional preproduction detectors. Using the specific experience from one production site as an example, we discuss how the quality controls make use of independent hardware and trained personnel to ensure fast and reliable production. Preliminary results on the construction status of CMS GEM detectors are presented.
A forward muon detector (ME0) has been proposed for the installation in the CMS endcap muon system in the region 2.0 < |η| < 2.8, to increase the muon acceptance. This region is characterized by a ...very harsh radiation environment, which can reach rates up to few hundreds of kHz/cm 2 . The technology proposed for the ME0 station is Triple-Gas Electron Multiplier (Triple-GEM), which has already been qualified for the operation in the CMS muon system. However an additional set of studies focused on the discharge probability is necessary for the ME0 station, due to the characteristic radiation environment mentioned above. A test was carried out in 2017 at the CERN High energy AcceleRator Mixed (CHARM) facility, with the aim of giving an estimation of the discharge probability of Triple-GEM detectors in a very intense radiation environment, similar to the one in the CMS muon system. A dedicated study with a standalone Geant4 simulation program was performed in order to evaluate the behavior of the detector exposed to the CHARM field. The geometry of the detector has been carefully reproduced, as well as the background field present in the facility. This paper will present the results obtained from the Geant4 simulation, in terms of sensitivity of the detector to the CHARM environment, together with the analysis of the energy deposited in the gas gaps.
In this paper we report on the current status of studies on the expected performance for a detector designed to operate in a muon collider environment. Beam-induced backgrounds (BIB) represent the ...main challenge in the design of the detector and the event reconstruction algorithms. The current detector design aims to show that satisfactory performance can be achieved, while further optimizations are expected to significantly improve the overall performance. We present the characterization of the expected beam-induced background, describe the detector design and software used for detailed event simulations taking into account BIB effects. The expected performance of charged-particle reconstruction, jets, electrons, photons and muons is discussed, including an initial study on heavy-flavor jet tagging. A simple method to measure the delivered luminosity is also described. Overall, the proposed design and reconstruction algorithms can successfully reconstruct the high transverse-momentum objects needed to carry out a broad physics program.
Among the post-LHC generation of particle accelerators, the muon collider represents a unique machine with capability to provide very high energy leptonic collisions and to open the path to a vast ...and mostly unexplored physics programme. However, on the experimental side, such great physics potential is accompanied by unprecedented technological challenges, due to the fact that muons are unstable particles. Their decay products interact with the machine elements and produce an intense flux of background particles that eventually reach the detector and may degrade its performance. In this paper, we present technologies that have a potential to match the challenging specifications of a muon collider detector and outline a path forward for the future R&D efforts.
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