Run 3

Shape-shifting collisions probe secrets of early Universe

The first high-energy collisions between light nuclei at the Large Hadron Collider confirm the unusual “bowling-pin” shape of neon nuclei and offer up a new tool to study the extreme state of matter produced in the aftermath of the Big Bang.

18 September 2025

Bowling balls vs. bowling pins? ATLAS studies the unique shape of neon ions

The ATLAS Collaboration today presented their first study of oxygen and neon collisions at the Initial Stages conference, including first measurements of elliptic flow.

8 September 2025

ATLAS closes in on rare Higgs decays

The ATLAS Collaboration finds evidence of Higgs-boson decays to muons and improves sensitivity to Higgs-boson decays to a Z boson and a photon.

7 July 2025

ATLAS takes a breath of oxygen

The ATLAS Experiment at CERN dives into uncharted waters, recording its first-ever collisions of oxygen and neon ions. These are not your typical heavy-ion collisions. Oxygen and neon nuclei are far smaller than lead – the LHC’s usual candidate for ion runs – and offer physicists exciting new opportunities to study the strong force.

1 July 2025

ATLAS sets record limits on Higgs self-interaction using Run 3 data

A new study of the Higgs boson marks the first ATLAS measurement based on over 300 fb⁻¹ of proton–proton collision data, achieving an expected sensitivity comparable to that of the full Run 2 combination across all Higgs boson pair production channels.

22 May 2025

Evolving ATLAS conditions data architecture for LHC Runs 3 and 4

For Run 3 of the LHC (2022–ongoing), the ATLAS Collaboration decided to change how it stores and processes conditions data. The significant efforts that went into this change – and the motivations for them – were presented at the 26th International Conference on Computing in High Energy and Nuclear Physics in May.

22 June 2023

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.

24 May 2023

ATLAS moves into top gear for Run 3

The ATLAS Collaboration has just released its first Run 3 measurements, studying data collected in the first half of August 2022. Researchers have measured the interaction strength (or cross-section) of two well-known processes: the production of a pair of top quarks and the production of a Z boson.

30 November 2022

ATLAS Experiment records “first physics” at new high-energy frontier

“We have proton collisions in the ATLAS experiment.” At 16.47 CEST, the Large Hadron Collider (LHC) officially kicked off its third period of operation (Run 3). The LHC is colliding proton beams at a world-record-breaking energy of 13.6 tera electron volts (TeV). The higher beam energy and intensity of Run 3 will allow the ATLAS experiment to push the very limits of its physics research.

5 July 2022

LHC Run 3: physics at record energy starts tomorrow

The Large Hadron Collider is ready to once again start delivering proton collisions to experiments, this time at an unprecedented energy of 13.6 TeV, marking the start of the accelerator’s third run of data taking for physics.

4 July 2022

ATLAS Pixel detector readies to tackle Run 3

The ATLAS experiment at the Large Hadron Collider (LHC) is on the eve of a new data harvest with the restart of the LHC for Run 3. The upcoming four-year run will provide a dataset nearly twice the size of what was collected in Run 2 (2015–2018).

1 July 2022

Countdown to physics: Beams splash in the ATLAS experiment

After over three years of upgrade and maintenance work, proton beams are back in the Large Hadron Collider! Friday 22 April 2022 marked the start of the LHC’s third operation period (Run 3), which will see a record number of collisions in the ATLAS detector.

28 April 2022