CERN Accelerating science

ATLAS

ATLAS NSW Upgrade: preparing installation and commission of its first sector

The New Small Wheel (NSW) Upgrade it the most complex and challenging Phase-1 Upgrade project of ATLAS. As all the other upgrade projects for the LHC experiments, the goal is to meet the challenges of the High-Luminosity LHC era and to cope with the…

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The Higgs boson as a probe for new physics

The discovery of the Higgs boson has ushered in a new era of exploration at the Large Hadron Collider (LHC). Persistent tensions in the Standard Model (SM) of particle physics compel us to seek out physics beyond the SM (BSM) at the TeV scale, and…

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ATLAS trigger system meets the challenges of Run 2

The trigger system is an essential component of any collider experiment as it is responsible for deciding whether or not to keep an event from a given bunch-crossing interaction for later study. During Run 2 (2015 to 2018) of the Large Hadron…

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FASER experiment to look for long-lived particles

At its last meeting CERN’s Research Board approved a new experiment that will look for light and weakly interacting long-lived particles at the LHC. The ForwArd Search ExpeRiment (FASER) will search for particles that might be produced parallel to…

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A New Small Wheel for ATLAS is taking shape

In order to fully exploit the HL-LHC luminosities, the innermost stations, the so called Small Wheels (SW), of the ATLAS Muon Spectrometer need to be replaced, by two new detector assemblies called New Small Wheels (NSW). This upgrade is schedule to…

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The LS2 period for the ATLAS detector

The main upgrade activities are all aimed at enhancing the capability of the detector to trigger more efficiently on leptonic and hadronic signatures. In particular it is essential to preserve the ability to trigger efficiently on electron and muons…

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HL-LHC computational challenge for ATLAS and CMS experiments

The two general purpose LHC Experiments, ATLAS [1] and CMS [2], are going to be confronted with challenging experimental conditions at the High Luminosity LHC Run (HL-LHC), starting in 2026. In particular, computing systems will have to cope with…

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Particle colliders join the quest for dark energy.

The birth of a new science The beginning of the twentieth century was marked by two of the greatest scientific discoveries: quantum mechanics and the theory of relativity, which became the driving forces behind an array of new scientific…

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Higgs boson observed decaying to bottom quarks

Last month, the ATLAS and CMS collaborations jointly announced the discovery of the Higgs boson decaying into a matter-antimatter pair of bottom quarks. Previously, the Higgs boson has been observed decaying to photons, tau-leptons, and W and Z…

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Axion-like particle searches at the LHC

The Standard Model (SM) of Particle Physics is plagued by some longstanding conceptual and practical questions, and we have to go beyond the Standard Model to address them. A guiding principle of the Standard Model is that we should expect to see…

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