What can the polarisation of W and Z bosons tell us about the Higgs mechanism?🔬 ATLAS reports the first observation of 2 longitudinally polarised Z bosons jointly produced, and evidence for longitudinally polarised Z bosons in electroweak WZ production with two jets. atlas.cern/Updates/Brie...

Polarised bosons: a window into the Higgs mechanism

While the Higgs mechanism is best known for breaking electroweak symmetry and giving fundamental particles mass, it can also leave a distinctive imprint on the polarisation of certain particles. A mas...

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ATLAS Enters the High-Luminosity Era 🚀 On 27 June 2026, the LHC's third run ended, marking a major milestone in particle physics. The next several years will be devoted to transforming the LHC and ATLAS for the #HiLumiLHC. Read the Press Release⤵️ atlas.cern/Updates/Pres...

ATLAS enters the high-luminosity era

At 05:52 a.m. on 27 June 2026, the final protons of the Large Hadron Collider's third data-taking period circulated through the accelerator, bringing Run 3 to a close and marking the end of a remarkab...

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The ATLAS Collaboration is deeply saddened to learn of the passing of François Englert, whose pioneering theoretical work transformed our understanding of the fundamental laws of nature.

Join scientists, live from the CERN Control Centre, as the Large Hadron Collider (#LHC) delivers its last collisions to its experiments before it is transformed into a high luminosity machine. #HiLumiLHC 📍LIVE on Facebook & YouTube 📆 11 June, 5:00 PM CEST 🔗 youtube.com/live/oVwzDcj...

LIVE LHC Season Finale, up next...

YouTube video by CERN

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This week, a new #HeavyIon run began at the Large Hadron Collider, recreating the extreme conditions of the early #Universe. Here we see event-displays from the LHC experiments: @atlasexperiment.bsky.social, @cmsexperiment.bsky.social, ALICE Experiment, @lhcb.bsky.social.

That's a wrap on protons at the LHC! 💥 Today, the ATLAS experiment closed the chapter on proton-proton data-taking at the LHC. Since 2010, ATLAS has recorded over 500 fb⁻¹ of proton collision data – an incredible dataset that will enable high-precision measurements and searches for new physics.

A rare trio of particles emerges at the #LHC! 🎆 For the first time at the LHC, the ATLAS Collaboration has found evidence that two Z bosons can be produced alongside a photon (ZZγ). Read the new physics briefing to learn more ⤵️ atlas.cern/Updates/Brie...

A new trio: ATLAS finds first evidence of ZZy production

The ATLAS Collaboration reports the first evidence of the simultaneous production of a photon and two neutral Z bosons at the LHC. The electroweak sector of the Standard Model combines the weak intera...

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What happens when four force-carrying particles interact at once? The ATLAS Experiment at @cern.bsky.social has mapped these rare "four-way intersections" of the weak force – among the most sensitive places to look for new physics beyond the Standard Model. 🔗 Learn more atlas.cern/Updates/Brie...

The ATLAS Collaboration has turned the Large Hadron Collider into a #cosmicray lab 🌌 By colliding protons with oxygen ions, physicists are recreating interactions that happen high in Earth’s atmosphere, where cosmic rays strike and produce particle showers. 🔗 atlas.cern/Updates/Brie...

ATLAS turns into a cosmic-ray laboratory with proton-oxygen collisions

The ATLAS Collaboration reports its first measurement of proton-oxygen collisions at the Large Hadron Collider (LHC). These results transform the ATLAS experiment into a cosmic-ray laboratory, helping...

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The ATLAS Collaboration reports the first evidence of Higgs-boson production at high transverse momentum in decays to a pair of bottom quarks. ✨️ The result opens a new regime for studying Higgs interactions and searching for new phenomena 🔗 atlas.cern/Updates/Brie...

ATLAS spots rare high-energy Higgs bosons for the first time

The ATLAS Collaboration reports the first evidence of Higgs-boson production at high transverse momentum in decays to a pair of bottom quarks. Almost 15 years since its discovery by the ATLAS and CMS ...

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ATLAS sets strong limits on #supersymmetry Using machine-learning techniques, the ATLAS Collaboration has searched deep for signs of particles that could help answer some of the greatest mysteries of physics Find out more: home.cern/news/news/ph... @atlasexperiment.bsky.social #LHC

🔬 March means one thing for particle physicists: Moriond. At Moriond 2026, ATLAS will debut 45 new analyses, from precision studies of the #Higgs and top quark to record searches for supersymmetry and other new physics. See the full list of results as it grows ⤵️ atlas.cern/Updates/News...

Summary of new ATLAS results from Moriond 2026

For particle physicists, March means one thing: Moriond. Every spring, theorists and experimentalists from around the world gather at the Rencontres de Moriond conferences to present their latest resu...

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Collision season begins! Over the weekend, the ATLAS Experiment recorded its first 13.6 TeV proton collisions of 2026. These event displays capture the start of the final run of the current Large Hadron Collider before its transformation to the High-Luminosity LHC. 🚀 Learn more: cern.ch/run3-2026

Tune in today at 11 AM CET for a live #LHC Seminar on new results in the search for Supersymmetry at @cern.bsky.social ! 🕚️ Watch live: cern.ch/atlas-webinar

It's time for physics! ⚛️ Stable particle beams returned to the Large Hadron Collider (LHC) at 15:58 CET on Saturday, 7 March, marking the start of the final run of #LHCRun3.

The ATLAS Experiment Thesis Awards celebrate exceptional doctoral research and the vital contributions students make to #particlephysics. Meet this year’s recipients, representing institutions across the global ATLAS community ⤵️ atlas.cern/Updates/News...

ATLAS 2025 Thesis Awards spotlight the “soul” of the Collaboration

The 2025 ATLAS Thesis Award ceremony. From left to right: ATLAS Collaboration Board Chair Davide Constanzo; ATLAS Thesis Awards Committee Chair Jean-François Arguin; ATLAS Thesis Award winners Elena M...

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Deep into the detector 👷 Today’s #PhotoOfTheWeek features the @atlasexperiment.bsky.social detector during the year-end technical stop (YETS) – a brief winter switch-off that allows for essential maintenance and upgrades on equipment and detectors, preparing them for the following physics run.

How do you measure a confetti cannon of particles? 🎉 Physicists at the ATLAS Experiment at @cern.bsky.social have pioneered a novel technique using top-quark decays to calibrate particle "jets" - the most common "footprints" left by #LHC collisions! Learn more ⤵️ atlas.cern/Updates/Brie...

Getting to the top of jet calibration

When particles burst from an LHC collision, they rarely leave a simple, single trail for physicists to follow. More often, they are high-energy quarks and gluons that erupt into jets, collimated spray...

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Here our scientists are testing the robotic handling of a vacuum module in the ATLAS cavern, part of the preparations for the operation of the High-Luminosity #LHC, the successor to CERN’s flagship accelerator.

The top quark’s large mass means it interacts most strongly with the Higgs field. By studying its pair production alongside a Higgs boson – a process that accounts for just 1% of all Higgs – researchers are learning about the origin of particle masses. Learn more ⤵️ atlas.cern/Updates/Brie...

ATLAS maps the top quark–Higgs boson interaction with multileptons

One of the central questions in particle physics is how fundamental particles acquire mass. The top quark, as the heaviest known elementary particle, interacts most strongly with the Higgs boson. As s...

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This year, for the #InternationalDayofWomenandGirlsinScience, we’re celebrating the “sparks” that ignite careers in physics. ⚛️⁠ ⁠ We asked four ATLAS experiment researchers to share what first inspired them. The stories of these women show that the spark for physics can come from anywhere! 👇

Heavy, energetic and fast-decaying — the #topquark’s properties make it an incredible tool for searching for new particles at high energy. Using an ingenious new technique, ATLAS physicists at @cern.bsky.social are now exploring single-top collisions with high precision ⤵️ atlas.cern/Updates/Brie...

Transforming sensitivity to new physics with single-top-quark events

The top quark, the heaviest known elementary particle, has captivated physicists since its discovery in the 1990s and holds a privileged place within the Standard Model of particle physics. It has a v...

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Happy #PrideinSTEMDay! 🏳️‍🌈🏳️‍⚧️ ATLAS proudly celebrates the incredible diversity of our scientific community. Our varied backgrounds, perspectives and identities drive excellence in research. We are committed to advancing the recognition and representation of our LGBTQ+ colleagues — today and every day.

Heavy-ion season is here! 💥⁠ ⁠ The ATLAS Experiment at @cern.bsky.social has recorded its first lead-lead collisions of 2025, marking the start of three weeks of heavy-ion running at 5.36 TeV per nucleon pair.⁠ Take a look at some of our first spectacular event displays!⁠

🎤 Are you passionate about science? Show us! 😉 To mark the 20th anniversary of FameLab International, CERN is teaming up with FameLab to invite you to share your love for science and win fantastic prizes.

Curiosity drives discovery!🌌 The ATLAS Experiment @cern.bsky.social brings together thousands of scientists and engineers from around the world to explore the building blocks of the Universe. 🎥 Watch our new introductory video, available in 6 languages on YouTube. www.youtube.com/watch?v=6UqW...

Mapping the Secrets of the Universe | Inside the ATLAS Experiment

YouTube video by ATLAS Experiment

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A rare sight at the LHC 👀 The ATLAS Collaboration at @cern.bsky.social reports its first observation of WWγ production — a rare process where two W bosons and a photon are produced together. 🔗 Learn more: atlas.cern/Updates/Brie...

Shining light on the Weak force: ATLAS observes WWγ production

The ATLAS Collaboration reports its first observation of WWγ production – a rare process involving the simultaneous production of two W bosons and a photon. The weak force is one of the four fundament...

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Congratulations to ATLAS Physicist Mounia Laassiri (Brookhaven National Laboratory) on being named a laureate of the 2025 UNESCO–AI Fozan Prize for the Promotion of Young Scientists in STEM! 🔗 Learn more: www.unesco.org/en/articles/...

Four charm quarks, one exotic state: the X(6900) tetraquark. The ATLAS Collaboration at @cern.bsky.social takes a deep dive into the all-charm tetraquark, marking a key step toward understanding exotic bound states of quarks. Learn more ⤵️ atlas.cern/Updates/Brie...

ATLAS takes a closer look at the all-charm tetraquark

The strong force, unrivaled in strength yet confined to minuscule distances, produces unique bound states of quarks known as quarkonia. These are the strong-force equivalent of the hydrogen atom, cons...

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What if we could turn the LHC into a lepton–proton collider? ✨ Thanks to rare quantum fluctuations, protons can briefly contain lepton–antilepton pairs. This allows ATLAS physicists to study lepton–proton collisions, opening a new door in the search for leptoquarks! ⤵️ atlas.cern/Updates/Brie...

Turning the LHC into a Lepton-Proton Collider in the search for leptoquarks

All matter in the universe is made up of just two fundamental building blocks: quarks and leptons. Intriguingly, both have three distinct families or “generations”. For example, the electron and its a...

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