16 research outputs found
Performance of a Large-Area GEM Detector Prototype for the Upgrade of the CMS Muon Endcap System
Gas Electron Multiplier (GEM) technology is being considered for the forward
muon upgrade of the CMS experiment in Phase 2 of the CERN LHC. Its first
implementation is planned for the GE1/1 system in the region of the muon endcap mainly to control muon level-1 trigger rates
after the second long LHC shutdown. A GE1/1 triple-GEM detector is read out by
3,072 radial strips with 455 rad pitch arranged in eight -sectors.
We assembled a full-size GE1/1 prototype of 1m length at Florida Tech and
tested it in 20-120 GeV hadron beams at Fermilab using Ar/CO 70:30 and
the RD51 scalable readout system. Four small GEM detectors with 2-D readout and
an average measured azimuthal resolution of 36 rad provided precise
reference tracks. Construction of this largest GEM detector built to-date is
described. Strip cluster parameters, detection efficiency, and spatial
resolution are studied with position and high voltage scans. The plateau
detection efficiency is [97.1 0.2 (stat)]\%. The azimuthal resolution is
found to be [123.5 1.6 (stat)] rad when operating in the center of
the efficiency plateau and using full pulse height information. The resolution
can be slightly improved by 10 rad when correcting for the bias due
to discrete readout strips. The CMS upgrade design calls for readout
electronics with binary hit output. When strip clusters are formed
correspondingly without charge-weighting and with fixed hit thresholds, a
position resolution of [136.8 2.5 stat] rad is measured, consistent
with the expected resolution of strip-pitch/ = 131.3 rad. Other
-sectors of the detector show similar response and performance.Comment: 8 pages, 32 figures, submitted to Proc. 2014 IEEE Nucl. Sci.
Symposium, Seattle, WA, reference adde
Quality control and beam test of GEM detectors for future upgrades of the CMS muon high rate region at the LHC
Gas Electron Multipliers (GEM) are a proven position sensitive gas detector technology which nowadays is becoming more widely used in High Energy Physics. GEMs offer an excellent spatial resolution and a high particle rate capability, with a close to 100% detection efficiency. In view of the high luminosity phase of the CERN Large Hadron Collider, these aforementioned features make GEMs suitable candidates for the future upgrades of the Compact Muon Solenoid (CMS) detector. In particular, the CMS GEM Collaboration proposes to cover the high-eta region of the muon system with large-area triple-GEM detectors, which have the ability to provide robust and redundant tracking and triggering functions. In this contribution, after a general introduction and overview of the project, the construction of full-size trapezoidal triple-GEM prototypes will be described in more detail. The procedures for the quality control of the GEM foils, including gain uniformity measurements with an x-ray source will be presented. In the past few years, several CMS triple-GEM prototype detectors were operated with test beams at the CERN SPS. The results of these test beam campaigns will be summarised
Quality control and beam test of GEM detectors for future upgrades of the CMS muon high rate region at the LHC
Gas Electron Multipliers (GEM) are a proven position sensitive gas detector technology which nowadays is becoming more widely used in High Energy Physics. GEMs offer an excellent spatial resolution and a high particle rate capability, with a close to 100% detection efficiency. In view of the high luminosity phase of the CERN Large Hadron Collider, these aforementioned features make GEMs suitable candidates for the future upgrades of the Compact Muon Solenoid (CMS) detector. In particular, the CMS GEM Collaboration proposes to cover the high-eta region of the muon system with large-area triple-GEM detectors, which have the ability to provide robust and redundant tracking and triggering functions. In this contribution, after a general introduction and overview of the project, the construction of full-size trapezoidal triple-GEM prototypes will be described in more detail. The procedures for the quality control of the GEM foils, including gain uniformity measurements with an x-ray source will be presented. In the past few years, several CMS triple-GEM prototype detectors were operated with test beams at the CERN SPS. The results of these test beam campaigns will be summarised
Status report on the CMS forward muon upgrade with large-size triple-GEM detectors
International audienceFor the High-Luminosity LHC (HL-LHC) phase the CMS GEM Collaboration is planning to install new large-size (990×220-455mm2) triple-GEM detectors, equipped with a new readout system, in the forward region of the muon system (1.5<; |η| <;2.2) of the CMS detector. Combining triggering and tracking functionalities the new triple-foil Gas Electron Multiplier (GEM) chambers will improve both the performance of the CMS muon trigger and the muon reconstruction/identification in CMS experiment. The addition of triple-GEM chambers to the forward region of the CMS muon system will add a necessary layer of redundancy. Starting from 2009 the CMS GEM Collaboration has built several small and full-size prototypes with different geometries, keeping improving the assembly techniques. All these prototypes have been tested in laboratories as well as with beam tests at the CERN Super Proton Synchrotron (SPS) and at Fermi National Accelerator Laboratory. In this contribution we will report on the status of the CMS upgrade project with triple-GEM chambers and its impact on the CMS performance as well as the hardware architectures and expected capability of the CMS GEM readout system
Upgrade of the CMS muon system with triple-GEM detectors
The CMS collaboration considers upgrading the muon forward region which is particularly affected by the high-luminosity conditions at the LHC. The proposal involves Gas Electron Multiplier (GEM) chambers, which are able to handle the extreme particle rates expected in this region along with a high spatial resolution. This allows to combine tracking and triggering capabilities, which will improve the CMS muon High Level Trigger, the muon identification and the track reconstruction. Intense R&D has been going on since 2009 and it has lead to the development of several GEM prototypes and associated detector electronics. These GEM prototypes have been subjected to extensive tests in the laboratory and in test beams at the CERN Super Proton Synchrotron (SPS). This contribution will review the status of the CMS upgrade project with GEMs and its impact on the CMS performanc
Impact of the Radiation Background on the CMS muon high-eta upgrade for the LHC high luminosity scenario
The Compact Muon Solenoid (CMS) experiment at the LHC is planning an upgrade of its muon
PoS(TIPP2014)086
detection system aiming to extend the muon detection capabilities in the forward region with the
installation of new muon stations based on Gas Electron Multiplier (GEM) and Resistive Plate
Chambers (RPC) technologies during the so-called Phase-2 upgrade scenario. With the imminent
increase on luminosity to 5 × 1034cm−2
s
−1
and center of mass collision energy of 14 TeV an
unprecedented and hostile radiation environment will be created, the most affected detectors will
be the ones located in the forward region where the intense flux of neutrons and photons could
potentially degrade the detector performance. Using FLUKA simulation the expected radiation
environment is estimated for the regions of interest, possible shielding scenarios are proposed and
the effect on the detector performance is discussed
The triple-GEM project for the phase 2 upgrade of the CMS muon system
In view of the high-luminosity phase of the LHC, the CMS Collaboration is considering the use of
Gas Electron Multiplier (GEM) detector technology for the upgrade of its muon system in the forward
region. With their ability to handle the extreme particle rates expected in that area, such micro-pattern
gas detectors can sustain a high performance and redundant muon trigger system. At the same time,
with their excellent spatial resolution, they can improve the muon track reconstruction and identifi-
cation capabilities of the forward detector, effectively combining tracking and triggering functions in
one single device. The present status of the CMS GEM project will be reviewed, highlighting importants
steps and achievements since the start of the R and D activities in 2009. The baseline design
of the triple-GEM detectors proposed for installation in different stations of the CMS muon endcap
system will be described, along with the associated frontend electronics and data-acquisition system.
The expected impact on the performance of the CMS muon system will be discussed, and results from
detector tests, both in the lab and in test beams will be presented