ATLAS measures ZZ production using Run-3 data and a new slim data format
The ATLAS Collaboration has just released a new measurement of the production cross section of two Z bosons. This highlight result examines data collected during Run 3 of the LHC and pioneers the use of PHYSLITE, a new, reduced data format that requires significantly less storage.
ATLAS searches for new phenomena using unsupervised machine learning for anomaly detection
In a new paper submitted to Phys. Rev. Lett., the ATLAS Collaboration pioneers the use of unsupervised machine learning to search for anomalous collision events which could be from new physics phenomena.
Quest for the curious magnetic monopole continues
In a new study presented at the EPS-HEP 2023 conference, the ATLAS Collaboration combed through the full LHC Run-2 dataset (recorded 2015-2018) in search for magnetic monopoles and HECOs (see Figure 1). The result places some of the tightest limits yet on the production rate of magnetic monopoles.
ATLAS releases comprehensive review of supersymmetric dark matter
In new results presented today, the ATLAS Collaboration provides its most comprehensive overview of the searches for weakly-interacting supersymmetric particles. By developing new search algorithms and exploiting machine learning techniques, researchers have probed deep into this difficult-to-reach territory.
Three’s no crowd: ATLAS measures tri-boson production
The ATLAS Collaboration has announced the first observation of two different tri-boson processes: the simultaneous production of a W boson with two photons (Wγγ) and the production of a W boson, a Z boson and a photon (WZγ). The production of a Z boson with two photons (Zγγ) was first observed in 2016 using data from LHC Run 1 (2010-2013). In a new publication, the ATLAS Collaboration expanded the scope of this initial observation using Run 2 data.
ATLAS hunts for new physics in the scattering of W bosons
Vector boson scattering processes play a special role within the Standard Model, as they are closely related to the Higgs mechanism and can proceed via an exchange of a Higgs boson. By studying these processes, ATLAS physicists are exploring multiple new-physics models, including anomalous self-interactions of the W bosons and extended Higgs sector with additional Higgs bosons.
Machine learning is revolutionising our understanding of particle “jets”
This week, ATLAS physicists presented four exciting new results about jet tagging using AI algorithms at the BOOST 2023 conference held at Lawrence Berkeley National Lab (USA).
Signal and noise
The ATLAS Collaboration has released two new results explaining how detector timing measurements and calorimeter signal calibration using artificial intelligence (AI) are being used to further improve the quality of data recorded by the experiment.
Summary of new ATLAS results from BOOST 2023
The 15th International Workshop on Boosted Object Phenomenology, Reconstruction, Measurements, and Searches at Colliders (BOOST 2023) kicks off today in Lawrence Berkeley National Lab, California (USA). The conference brings together experts from the LHC experiments and the theory community to discuss new approaches for using “jets” of particles in studies of Quantum Chromodynamics (QCD) and searches physics beyond the Standard Model.
News |
ATLAS sets record precision on Higgs boson’s mass
The new result is the most precise determination of the Higgs-boson mass yet, achieving a remarkable accuracy of 0.09% for this fundamental parameter.
ATLAS measures Higgs boson mass with unprecedented precision
This week, at the Lepton-Photon Conference in Melbourne (Australia), the ATLAS Collaboration presented its measurement of the Higgs-boson mass in studies of Higgs decays to two photons using the full LHC Run 2 dataset (“H→yy” or the diphoton channel), and a new combination of this measurement with the 2022 measurement of the Higgs-boson mass in studies of the Higgs decays to four leptons (the “H→4l channel”).
Summary of new ATLAS results from 2023 summer conferences
The summer conference season is here! While for some, summer means slowing down – for ATLAS researchers, it means the start of new conferences, with more new results to be presented! This season, experimental physics and theorists will be traveling to Melbourne, Australia, for the International Symposium on Lepton Photon Interactions at High Energies (Lepton Photon), and to Hamburg, Germany, for the European Physical Society Conference on High Energy Physics ( EPS-HEP).
News |
Giving collisions a new shape
When studying the shape of LHC collision events, physicists ask: how similar or different is their energy flow? The ATLAS Collaboration recently published a measurement of new collision event shapes in high-energy multijet events at the LHC.
ATLAS highlights from LHCP 2023
Over 300 physicists travelled to Belgrade (Serbia) for LHCP’s long-awaited return to in-person gatherings. Scientists from the ATLAS Collaboration presented several new results at the LHCP conference. These newly released results cover a broad range of physics topics, including precision measurements of the W± and Z bosons, evidence of the Higgs-boson decay into a Z boson and a photon, and searches for a new scalar particle.
News |
Not a jet all the way: is dark matter hiding in plain sight?
What happens if dark-matter particles are produced inside a jet of Standard-Model particles? This leads to a novel detector signature known as semi-visible jets! The ATLAS Collaboration has come up with a new search for semi-visible jets, looking for them in a general production mode where two protons interact by exchanging an intermediate particle, which is then converted into two jets.
LHC experiments see first evidence for rare Higgs boson decay into two different bosons
The ATLAS and CMS Collaborations have joined forces to report first evidence of the Higgs boson decaying into a Z boson and a photon.
LHC experiments see first evidence of a rare Higgs boson decay
ATLAS and CMS teamed up to find the first evidence of the rare process in which the Higgs boson decays into a Z boson, the electrically neutral carrier of the weak force, and a photon, the carrier of the electromagnetic force.
New high-precision measurements of W and Z boson properties
At the 2023 LHCP conference, ATLAS physicists presented precise new measurements of the W± and Z boson transverse momentum distributions at two centre-of-mass energies: 13 TeV and, for the first time, 5.02 TeV. These results give unprecedented information on these transverse-momentum shape spectra, providing crucial input for other studies of these bosons.
ATLAS measures the Higgs boson at 13.6 TeV
The ATLAS Collaboration just released new measurements of the production rate (or cross-section) of Higgs bosons at 13.6 TeV using data collected in the second half of 2022.
Summary of new ATLAS results from LHCP 2023
The eleventh annual conference on Large Hadron Collider physics (LHCP 2023) kicks off today in Belgrade (Serbia) signaling the return of this week-long event to its face-to-face format. The programme of this edition covers the wide spectrum of Large Hadron Collider physics and technology, from several final studies of the LHC Run-2 dataset (2015-2018) to detailed assessments of the upgraded accelerators and detectors for Run 3.
News |
ATLAS Live: Behind the Scenes at the Control Room
On 5 May at 4pm CEST, ATLAS physicists Dr. Stefanie Morgenstern and Dr. Liaoshan Shi will give a live tour of the ATLAS Control Room on the ATLAS and CERN Youtube Channels.
News |
ATLAS highlights from the Moriond 2023 conference
ATLAS researchers presented several new results at the recent Rencontres de Moriond conference, spanning over a decade of LHC data.
News |
ATLAS & CMS Physicists Recover Lost Higgs Boson
Scientists working on the Large Hadron Collider at CERN breathed a sigh of relief today, as the world-renowned Higgs boson returned to its showcase in the heart of the laboratory.
Blog |
Probing fundamental symmetries of nature with the Higgs boson
In the new results presented at the Moriond conferences, the ATLAS Collaboration tested the CP invariance of Higgs-boson interactions with vector bosons (W or Z bosons).
LHC passes a new milestone
The ATLAS Collaboration has just published the most precise measurement to date of the production cross section of top-quark pairs. The measured value is 829 ± 15 picobarns and has a relative uncertainty of just 1.8%.