The CMS Collaboration plans to equip the very forward muon system with triple-GEM detectors that can withstand the environment of the High-Luminosity LHC. This project is at the final stages of R&D ...and moving to production. An unprecedented large area of several 100 m
2
are to be instrumented with GEM detectors which will be produced in six different sites around the world. A common construction and quality control procedure is required to ensure the performance of each detector. The quality control steps will include optical inspection, cleaning and baking of all materials and parts used to build the detector, leakage current tests of the GEM foils, high voltage tests, gas leak tests of the chambers and monitoring pressure drop vs. time, gain calibration to know the optimal operation region of the detector, gain uniformity tests, and studying the efficiency, noise and tracking performance of the detectors in a cosmic stand using scintillators.
The CMS muon system includes in both the barrel and endcap region Resistive Plate Chambers (RPC). They mainly serve as trigger detectors and also improve the reconstruction of muon parameters. Over ...the years, the instantaneous luminosity of the Large Hadron Collider gradually increases. During the LHC Phase 1 ( similar to first 10 years of operation) an ultimate luminosity is expected above its design value of 10 super(34) cm super(-2)s super(-1) at 14 TeV. To prepare the machine and also the experiments for this, two long shutdown periods are scheduled for 2013-2014 and 2018-2019. The CMS Collaboration is planning several detector upgrades during these long shutdowns. In particular, the muon detection system should be able to maintain a low-pT threshold for an efficient Level-1 Muon Trigger at high particle rates. One of the measures to ensure this, is to extend the present RPC system with the addition of a 4th layer in both endcap regions. During the first long shutdown, these two new stations will be equipped in the region degree ' eta degree ' < 1.6 with 144 High Pressure Laminate (HPL) double-layer RPCs operating in avalanche mode, with a similar design as the existing CMS endcap chambers. Here, we present the upgrade plans for the CMS RPC system for the fist long shutdown, including trigger simulation studies for the extended system, and details on the new HPL production, the chamber assembly and the quality control procedures.
The Gas GainMonitoring (GGM) system of the Resistive Plate Chamber (RPC) muondetector in the Compact Muon Solenoid (CMS) experiment provides fast and accurate determinationof the stability in the ...working point conditions due to gas mixture changes in the closed looprecirculation system. In 2011 the GGM began to operate using a feedback algorithm to control theapplied voltage, in order to keep the GGM response insensitive to environmental temperature andatmospheric pressure variations. Recent results are presented on the feedback method used and onalternative algorithms.
The CMS experiment will install a RE4 layer of 144 new Resistive Plate Chambers (RPCs) on the existing york YE3 at both endcap regions to trigger high momentum muons from the proton-proton ...interaction. In this paper, we present the detailed procedures used in the production of new RPC gas gaps adopted in the CMS upgrade. Quality assurance is enforced as ways to maintain the same quality of RPC gas gaps as the existing 432 endcap RPC chambers that have been operational since the beginning of the LHC operation.
In this paper, we report a systematic study of multigap Resistive Plate Chambers (RPCs) for high- eta triggers in CMS. Prototype RPC modules with four- and six-gap structures have been constructed ...with phenolic high-pressure-laminated (HPL) plates and tested with cosmic muons and gamma rays irradiated from a 200-mCi super(137)Cs source. The detector characteristics of the prototype multigap RPCs were compared with those of the double-gap RPCs currently used in the CMS experiment at LHC. The mean values for detector charges of cosmic-muon signals drawn in the four- and six-gap RPCs for the efficiency values in the middle of the plateau were about 1.5 and 0.9 pC, respectively, when digitized with charge thresholds of 150 and 100 fC, respectively. They were respectively about one third and one fifth of that drawn in the current CMS doublegap RPC with a charge threshold of 200 fC. We concluded from the current R&D that use of the current phenolic-HPL multigap RPCs is advantageous to the high- eta triggers in CMS in virtue of the smaller detector pulses.
CMS iRPC FEB development and validation Gouzevitch, M.; El Sawy, M.; Alves, G.A. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
07/2024, Letnik:
1064
Journal Article
Recenzirano
Odprti dostop
In view of the High Luminosity upgrade of the CERN LHC, the forward CMS Muon spectrometer will be extended with two new stations of improved Resistive Plate Chambers (iRPC) covering the ...pseudorapidity range from 1.8 to 2.4. Compared to the present RPC system, the gap thickness is reduced to lower the avalanche charge, and an innovative 2D strip readout geometry is proposed. These improvements will allow iRPC detector to cope with higher background rates. A new Front-End-Board (FEB) is designed to readout iRPC signals with a threshold as low as 30fC and an integrated Time Digital Converter with a resolution of 30ps. In addition, the communication bandwidth is significantly increased by using optical fibers. The history, final design, certification, and calibration of this FEB are presented.
Improved resistive plate chambers for HL-LHC upgrade of CMS Samalan, A.; Thiel, M.; Asilar, E. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
03/2024, Letnik:
1060, Številka:
C
Journal Article
Pressure correction study for the CMS iRPC detector Abdelhameid, T.; Gouzevitch, M.; Tytgat, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2024, Letnik:
1059, Številka:
C
Journal Article
Aging studies for the CMS improved Resistive Plate Chambers Filho, M. Barroso Ferreira; Tytgat, M.; El Sawy, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
10/2023, Letnik:
1055
Journal Article
Recenzirano
For the High Luminosity (HL-LHC) upgrade an upgrade of the CMS detector is foreseen. One of the main projects is the development of the improved Resistive Plate Chamber (iRPC) detectors that will be ...installed in the forward region of CMS. To validate the performance of the new detector gaps with HL-LHC radiation levels, experimental tests have been conducted at the CERN Gamma Irradiation Facility (GIF++). One chamber equipped with electronics is studied and its parameters are monitored as a function of the accumulated charge.