If spotting one Higgs boson is interesting, what happens when you spot two? ATLAS researchers are looking for the production of two Higgs bosons using a new technique.

Using the full LHC Run-2 dataset, the ATLAS Collaboration measured Z boson production in association with both bottom (b) and charm (c) quarks, the latter for the first time in ATLAS.

New results released by the ATLAS Collaboration describe the significant advancements made in identifying electrons and photons.

In a groundbreaking new result, the ATLAS Collaboration has measured the W-boson width for the first time at the Large Hadron Collider (LHC).

The ATLAS Collaboration has just released its first measurements using LHC Run-3 data of the production rates (“cross sections”) of W and Z bosons.

In a new result presented at Moriond EW, physicists at the ATLAS Collaboration tested lepton flavour universality between muons and electrons. The precision of the result stands as the best yet-achieved in W-boson decays by a single experiment and surpasses the world average.

In a new result, researchers conducted a novel search of data collected during Run 2 of the LHC, searching for heavy new particles that could fit the 2HDM or 2HDM+S models.

In a new result, the ATLAS Collaboration reports the first evidence of a Higgs boson produced in association with a leptonically-decaying W or Z boson and decaying into a pair of tau leptons.

The ATLAS Collaboration has published three new results in this challenging area, using Boosted Decision Trees (BDTs) to isolate potential signals and ultimately set stringent constraints on the masses of SUSY particles.

The ATLAS Collaboration has measured the production cross section of the J/ψ and ψ(2S) charmonium states in terms of the transverse momentum and the rapidity. For both states, they examined the widest range of transverse momentum so far, thus providing new input for theoretical models.

The ATLAS and CMS Experiments at CERN have just released a new measurement of the mass of the top quark. The new result combines 15 previous measurements to give the most precise determination of the top quark mass to date.

In a new result from the ATLAS Collaboration, physicists observed – for the first time – quantum entanglement between a pair of quarks. This is the highest-energy measurement of entanglement to date.

The ATLAS Collaboration has released two brand-new results searching for di-Higgs events in the full LHC Run-2 dataset. In one, researchers looked for events where one Higgs boson decays into two bottom quarks and the other decays into two photons. In the other, they looked for events where one Higgs boson decays into two bottom quarks, and the other into two tau leptons or W/Z bosons, which subsequently decay into leptons.

The ATLAS Collaboration at CERN observes the production of top-quark pairs in proton-lead ion collisions. ATLAS’ new result confirms and builds upon an earlier observation made by the CMS Collaboration, expanding it into a new decay channel.

For the very first time, the ATLAS Collaboration has searched for dark jets that closely resemble QCD jets. Instead of originating from Standard-Model particles, these dark jets would be produced through a new, heavy particle called the Z' boson.

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.

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.

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.

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.

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.

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.

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).

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.

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”).

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.