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CMS

The CMS Trigger System for Run 3

Before the start of the LHC Run 3, CMS improved many aspects of its trigger system in order to boost the physics reach of the experiment. To select events of potential physics interest, the CMS trigger system divides the processing into two levels:…

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Upgrading the CMS Electromagnetic Calorimeter Readout Electronics for Phase-2

The CMS electromagnetic calorimeter (ECAL) was designed to provide excellent energy resolution for electrons and photons in the challenging, high-radiation environment of the Large Hadron Collider [1]. In particular, the excellent design energy…

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Testing silicon sensors for the CMS Endcap Calorimeter Upgrade

Introduction The upcoming upgrade of the LHC to the HL-LHC will pose significant challenges to the detectors due to the enhanced radiation levels and the increase in the number of pile-up interactions. To meet the increased demands, CMS has…

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CMS sails to explore new undiscovered territories

Run 3 started on July 5, 2022, and paused with the shutdown of the machine on Monday, November 28 at 6 a.m. CMS recorded an integrated luminosity of nearly 40/fb (see Fig. 1, making for a particularly fruitful startup run. Figure 1: Luminosity…

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ATLAS and CMS experiments looking forward to Run 3

On the 4th of July of 2022 we celebrated the 10th anniversary of the end of decades-long search for an experimental confirmation of the BEH mechanism, and the start of a new era. With the discovery of the Higgs boson, the last unknown fundamental…

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Start up of the ATLAS and CMS magnets

LS2 works and commissioning of the ATLAS Superconducting Magnets   In the last few years, the ATLAS superconducting magnets and associated systems have received extensive maintenance and upgrades. Following this, the magnets have recently been…

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Demonstrating the capabilities of a new GEM

During the LHC Long Shutdown 2 (2019-2021), many subsystems of the CMS experiment are being upgraded including its muon system. This is located on the outer part of the experiment and consists of various types of gaseous chambers. The muon system…

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Proton beams recorded at CMS pave the way for next LHC run

The Long Shutdown 2 (LS2) is almost over and CERN, along with the experiments at the Large Hadron Collider (LHC), is preparing to welcome the Run 3 next year. As part of the preparation for Run 3, during the last two weeks of October, LHC circulated…

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Successful installation of the CMS Pixel Tracker

In early 2019 the CMS Phase-1 Pixel detector was extracted from the underground cavern after successful completion of the LHC Run 2 data taking campaign. Its sub-detectors, the Barrel Pixel (BPIX) and Forward Pixel (FPIX) detectors, were stored cool…

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CMS experiment prepares for Run 3

The CMS experiment is one of the four large experiments at the LHC and a detailed description of the detector's inner and outer layers can be found here. The detector successfully operated with LHC collisions since 2010 leading to the Higgs boson…

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