In new results released this week, ATLAS physicists describe novel techniques used to accurately align the muon spectrometer.

The ATLAS Collaboration welcomes new management this month, with Andreas Hoecker (CERN) taking the lead as Spokesperson for the experiment.

At the ATLAS Early Career Scientist Board (ECSB), we have also had to adapt in order to best represent and assist the early career scientists in our collaboration. One of the biggest changes was moving all of our events in the second half of 2020 to be entirely virtual.

ATLAS PhD students are a key cohort of the Collaboration, making unique and crucial contributions to the experiment while working on their degree. Every year, their work is celebrated in the context of the ATLAS Thesis Awards.

The 2020 ATLAS Outstanding Achievement Awards ceremony was held online on 11 February 2021. Established in 2014, the awards recognise outstanding contributions in support of the ATLAS experiment, covering all areas except physics analysis. 

ATLAS finds first evidence of the Higgs boson decaying to two leptons and a photon. This is one of the rarest Higgs boson decays yet seen at the LHC, with striking features that presented unique challenges for the ATLAS experiment.

ATLAS PhD student Meirin Oan Evans explores how the University of Sussex is incorporating ATLAS Open Data into their teaching – and shares his experience using this incredible resource.

Despite the huge challenges of the COVID-19 pandemic, last year saw excellent successes for the ATLAS Collaboration, including first-of-a-kind physics results and great headway made on detector upgrades.

New results from the ATLAS Collaboration focus on different production modes of the Higgs boson decaying into b-quarks, capitalising on the power of machine learning to better discriminate this particular process from other proton collision events.

Journey into the ATLAS Experiment! On Thursday 26th November, Prof. Daniela Bortoletto gave a live public talk on Youtube describing how particle detectors like ATLAS find elementary particles.

The ATLAS Collaboration has just released a collection of 200 software packages that make up the Trigger and Data Acquisition System (TDAQ). With this new release, most ATLAS software is now open – reinforcing the Collaboration’s ongoing commitment to open science.

A new result from the ATLAS Collaboration, released for the Higgs 2020 conference, aims at enriching the Higgs picture by studying its WW* decays.

Dark Matter plays a crucial role in the evolution of our Universe. On Thursday 29th October, Dr. Christian Ohm gave a live public talk on Youtube on the extraordinary mystery of Dark Matter.

One of the great unexplained mysteries is the nature of dark matter. So far, its existence has only been established through gravitational effects observed in space; no dark-matter particles with the needed properties have (yet) been detected. Could the Higgs boson be the key to their discovery?

ATLAS scientists are implementing a new strategy in the search for physics beyond the Standard Model – one that combines measurements across the full spectrum of the Collaboration's research programme.

ATLAS researchers are broadening their extensive search programme to look for more unusual signatures of unknown physics, such as long-lived particles. A theory that naturally motivates long-lived particles is supersymmetry (SUSY). A new search from the ATLAS Collaboration – released this week for the 5th International Conference on Particle Physics and Astrophysics (ICPPA-2020) – looks for the superpartners of the electron, muon and tau lepton

In 2017, the ATLAS and CMS Collaborations announced the detection of a never-before-observed process: vector boson scattering.

It was in 2014, just a few months after my transition from ALICE to ATLAS, that I saw the mock-up for the first time: a full-scale wooden reproduction of the central portion of the ATLAS experiment, measuring some 8 metres high and wide.

With new data from the LHC, ATLAS physicists have measured jet-quenching phenomena in the quark–gluon plasma with help of Z bosons.

As major players in the field of particle physics, the LHC collaborations contributed many new results, most of which exploited the full Run 2 dataset, recorded in 2015 to 2018. ATLAS physicists contributed 35 new results, and gave 85 talks in the parallel and plenary sessions. Their contributions spanned a wide range of topics, from precision measurements and searches for new phenomena to detector performance and R&D, as well as diversity and outreach.

During the International Conference on High-Energy Physics (ICHEP 2020), the ATLAS Collaboration presented the first observation of photon collisions producing pairs of W bosons, elementary particles that carry the weak force, one of the four fundamental forces. The result demonstrates a new way of using the LHC, namely as a high-energy photon collider directly probing electroweak interactions. It confirms one of the main predictions of electroweak theory – that force carriers can interact with themselves – and provides new ways to probe it.

The ATLAS Collaboration has announced the first observation of two W bosons produced from the scattering of two photons — particles of light – at the International Conference on High-Energy Physics (ICHEP 2020).

The ATLAS and CMS experiments at CERN announce new results which show that the Higgs boson decays into two muons. These new results have pivotal importance for fundamental physics because they indicate for the first time that the Higgs boson interacts with second-generation elementary particles.

The ATLAS Collaboration has released a new study into a key building block of matter: leptons. This type of particle comes in three different families (flavours) and, according to the Standard Model, should follow strict rules. For instance, except for their mass, leptons of different flavours have identical properties – a feature known as lepton flavour universality. This was recently corroborated by a key measurement of the W-boson decay rates into leptons by the ATLAS Collaboration.

Physicists can study Higgs-boson couplings in several ways: by measuring the rates of different Higgs boson production mechanisms and decays, and also by studying the particle’s kinematic properties. The ATLAS Collaboration has just presented precise new measurements of these key quantities. Several of these measurements were updated to use the full LHC Run 2 dataset (2015–2018), to provide the best precision to date.