27 research outputs found
Machine Learning based tool for CMS RPC currents quality monitoring
The muon system of the CERN Compact Muon Solenoid (CMS) experiment includes
more than a thousand Resistive Plate Chambers (RPC). They are gaseous detectors
operated in the hostile environment of the CMS underground cavern on the Large
Hadron Collider where pp luminosities of up to
are routinely achieved. The CMS RPC system
performance is constantly monitored and the detector is regularly maintained to
ensure stable operation. The main monitorable characteristics are dark current,
efficiency for muon detection, noise rate etc. Herein we describe an automated
tool for CMS RPC current monitoring which uses Machine Learning techniques. We
further elaborate on the dedicated generalized linear model proposed already
and add autoencoder models for self-consistent predictions as well as hybrid
models to allow for RPC current predictions in a distant future
Plant polyprenols reduce demyelination and recover impaired oligodendrogenesis and neurogenesis in the cuprizone murine model of multiple sclerosis
Ablation of olfactory bulb glutamatergic neurons induces depressive-like behaviors and sleep disturbances in mice
Study of Thin Double-Gap RPCs for the CMS Muon System
High-sensitivity double-gap phenolic resistive plate chambers (RPCs) are studied for the Phase-2 upgrade of the Compact Muon Solenoid (CMS) muon system at high pseudorapidity η. Whereas the present CMS RPCs have a gas gap thickness of 2 mm, we propose to use thinner gas gaps, which will improve the performance of these RPCs. To validate this proposal, we constructed double-gap RPCs with two different gap thicknesses of 1.2 and 1.4 mm by using high-pressure laminated plates having a mean resistivity of about 5 à 10 Ω-cm. This paper presents test results using cosmic muons andCs gamma rays. The rate capabilities of these thin-gap RPCs measured with the gamma source exceed the maximum rate expected in the new high-η endcap RPCs planned for future Phase-2 runs of the Large Hadron Collider (LHC)
Study of Thin Double-Gap RPCs for the CMS Muon System
International audienceHigh-sensitivity double-gap phenolic resistive plate chambers (RPCs) are studied for the Phase-2 upgrade of the Compact Muon Solenoid (CMS) muon system at high pseudorapidity η. Whereas the present CMS RPCs have a gas gap thickness of 2 mm, we propose to use thinner gas gaps, which will improve the performance of these RPCs. To validate this proposal, we constructed double-gap RPCs with two different gap thicknesses of 1.2 and 1.4 mm by using high-pressure laminated plates having a mean resistivity of about 5 à 10 Ω-cm. This paper presents test results using cosmic muons andCs gamma rays. The rate capabilities of these thin-gap RPCs measured with the gamma source exceed the maximum rate expected in the new high-η endcap RPCs planned for future Phase-2 runs of the Large Hadron Collider (LHC)
Experiences from the RPC data taking during the CMS RUN-2
International audienceThe CMS experiment recorded 177.75 fbâ1 of proton-proton collision data during the RUN-1 and RUN-2 data taking period. Successful data taking at increasing instantaneous luminosities with the evolving detector configuration was a big achievement of the collaboration. The CMS RPC system provided redundant information for the robust muon triggering, reconstruction, and identification. To ensure stable data taking, the CMS RPC collaboration has performed detector operation, calibration, and performance studies. Various software and related tools are developed and maintained accordingly. In this paper, the overall performance of the CMS RPC system and experiences of the data taking during the RUN-2 period are summarised
Upgrade of the CMS resistive plate chambers for the high luminosity LHC
International audienceDuring the upcoming High Luminosity phase of the Large Hadron Collider (HL-LHC), the integrated luminosity of the accelerator will increase to 3000 fb. The expected experimental conditions in that period in terms of background rates, event pileup, and the probable aging of the current detectors present a challenge for all the existing experiments at the LHC, including the Compact Muon Solenoid (CMS) experiment. To ensure a highly performing muon system for this period, several upgrades of the Resistive Plate Chamber (RPC) system of the CMS are currently being implemented. These include the replacement of the readout system for the present system, and the installation of two new RPC stations with improved chamber and front-end electronics designs. The current overall status of this CMS RPC upgrade project is presented
CMS RPC activities during LHC LS-2
International audienceThe second LHC long shutdown period (LS2) is an important opportunity for the CMS Resistive Plate Chambers (RPC) to complete their consolidation and upgrade projects. The consolidation includes detector maintenance for gas tightness, HV (high voltage), LV (low voltage) and slow control operation. All services for the RPC Phase-2 upgrade: improved RPC in stations RE3/1 and RE4/1, were anticipated for installation to LS2. This paper summarises the RPC system maintenance and upgrade activities
Improved-RPC for the CMS muon system upgrade for the HL-LHC
International audienceDuring Phase-2 of the LHC, known as the High Luminosity LHC (HL-LHC), the accelerator will increase its instantaneous luminosity to 5 Ă 1034 cmâ2 sâ1, delivering an integrated luminosity of 3000 fbâ1 over 10 years of operation starting from 2027. In view of the HL-LHC, the CMS muon system will be upgraded to sustain efficient muon triggering and reconstruction performance. Resistive Plate Chambers (RPCs) serve as dedicated detectors for muon triggering due to their excellent timing resolution, and will extend the acceptance up to pseudorapidity values of |η|=2.4. Before Long Shutdown 3 (LS3), the RE3/1 and RE4/1 stations of the endcap will be equipped with new improved Resistive Plate Chambers (iRPCs) having different design and geometry than the present RPC system. The iRPC geometry configuration improves the detector's rate capability and its ability to survive the harsh background conditions of the HL-LHC . Also, new electronics with excellent timing performances (time resolution of less than 150 ps) are developed to read out the RPC detectors from both sides of the strips to allow for good spatial resolution along them. The performance of the iRPC has been studied with gamma radiation at the Gamma Irradiation Facility (GIF++) at CERN. Ongoing longevity studies will help to certify the iRPCs for the HL-LHC running period. The main detector parameters such as the current, rate and resistivity are regularly monitored as a function of the integrated charge. Preliminary results of the detector performance will be presented