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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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Jet Substructure as a powerful probe of Quantum Chromodynamics

Jet substructure (JSS) has emerged as a powerful framework for studying the Standard Model (SM) and provides a key set of tools for probing nature at the highest energy scales accessible by terrestrial experiments. While not an experimental or…

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Problems and Solutions: The CMS ECAL lessons

The story starts in September 2022 while, during the ECAL Operations meeting our veteran electronics expert, Evgueni Vlassov reported that the voltage in one of the control cards was unstable. He prophetically proposed that the cause might be water…

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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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MILLIQAN gets ready to have a look at the dark

The milliQan collaboration is on track to finish the installation and commissioning of their Run 3 detector before the end of the YETS, Components of both the “bar” and “slab” detectors have been placed in a tunnel above the CMS experimental cavern…

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The Phase-2 Upgrade of the CMS Data Acquisition system

Even though Run-3 data taking has only just started, the preparations for the next phase of the LHC physics programme are well under way. Just like the LHC, during LS3 many of the LHC experiments will receive significant upgrades.  In order to…

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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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From Despair to Discovery

The Ultimate Higgs Discovery Machine: The excitement amongst particle physicists around the world was palpable when the LHC, a proton accelerator twenty years in the making, started its commissioning phase on 10th September 2008. With 7 TeV protons…

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Solving New Puzzles with the Higgs Boson

… to make an end is to make a beginning. The end is where we start from. T.S. Eliot, Little Gidding   You might think that particle physics has accomplished its goals with the discovery of the last piece of the Standard Model jigsaw puzzle, the…

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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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