dark matter

When jets go dark: identifying elusive "dark jets" at ATLAS

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.

6 September 2023

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.

22 August 2023

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.

26 May 2023

Using the Higgs boson to search for dark photons

The ATLAS Collaboration has been looking for signs of dark photons in data collected by the experiment during LHC Run 2 (2015-2018). Their newest search targets, for the first time in ATLAS, the production of a Higgs boson in association with a Z boson, with subsequent decay of the Higgs into a photon and a dark photon.

15 September 2022

Looking for the invisible with the Higgs boson

According to the Standard Model, most particles get their mass through an interaction with the Higgs field. If dark-matter particles acquire their mass in the same way, a Higgs boson created in an LHC collision might sometimes decay into a pair of “invisible” dark-matter particles. The ATLAS Collaboration has released a new search for invisible Higgs-boson decays using the full Run-2 dataset.

17 February 2022

ATLAS Live talk: Searching for Dark Matter with Dr. Christian Ohm

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.

31 October 2020

ATLAS uses the Higgs boson as a tool to search for 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?

29 October 2020

Jetting into the dark side: a precision search for dark matter

The nature of dark matter remains one of the great unsolved puzzles of fundamental physics. Many theoretical scenarios postulate that dark matter particles could be produced in the intense high-energy proton–proton collisions of the LHC. While the dark matter would escape the ATLAS detector unseen, it could occasionally be accompanied by a visible jet of particles radiated from the interaction point. Today, at the International Conference in High-Energy Physics (ICHEP 2020), ATLAS presented a new search for novel phenomena in collision events with jets and high missing transverse momentum (MET).

27 July 2020

Probing Dark Matter with the Higgs boson

Could the Higgs boson decay into dark matter? As dark matter does not interact directly with the ATLAS detector, physicists look for signs of “invisible particles”, inferred through momentum conservation of the proton–proton collision products. The ATLAS Collaboration searched the full LHC Run 2 dataset, setting the strongest limits on the Higgs boson decaying to invisible dark-matter particles to date.

21 April 2020

ATLAS sets strong constraints on supersymmetric dark matter

One of the most complete theoretical frameworks that includes a dark matter candidate is supersymmetry. Dark matter is an unknown type of matter present in the universe, which could be of particle origin. Many supersymmetric models predict the existence of a new stable, invisible particle - the lightest supersymmetric particle (LSP) – which has the right properties to be a dark matter particle. The ATLAS Collaboration has recently reported two new results on searches for an LSP where it exploited the experiment’s full “Run 2” data sample taken at 13 TeV proton-proton collision energy. The analyses looked for the pair production of two heavy supersymmetric particles, each of which decays to observable Standard Model particles and an LSP in the detector.

8 April 2019

Searching for Dark Matter with the ATLAS detector

When we look around us, at all the things we can touch and see all of this is visible matter. And yet, this makes up less than 5% of the universe.

5 March 2019

New data-collection method aids in the hunt for new physics

What do you do when you produce more data than you can handle? This might seem like a strange question for experimental physicists, but it’s a problem that the ATLAS detector faces every day. While the LHC continues to produce ever-higher rates of proton collisions, the detector can only record data at a fixed rate. Therefore, tough choices must be made about what events to keep. This is not a decision made lightly – what if the thrown-away data contain some long-sought new particles beyond those of the Standard Model.

21 March 2018

The invisible plan

As the Large Hadron Collider (LHC) smashes together protons at a centre-of-mass energy of 13 TeV, it creates a rich assortment of particles that are identified through the signature of their interactions with the ATLAS detector. But what if there are particles being produced that travel through ATLAS without interacting? These “invisible particles” may provide the answers to some of the greatest mysteries in physics.

17 July 2017

Particle-hunting at the energy frontier

There are many mysteries the Standard Model of particle physics cannot answer. Why is there an imbalance between matter and anti-matter in our Universe? What is the nature of dark matter or dark energy? And many more. The existence of physics beyond the Standard Model can solve some of these fundamental questions. By studying the head-on collisions of protons at a centre-of-mass energy of 13 TeV provided by the LHC, the ATLAS Collaboration is on the hunt for signs of new physics.

21 March 2017

Further progress in the quest for SUSY particles

ATLAS physicists have been eagerly searching the collected data for evidence of the production of the supersymmetric top quark (squark). Recent ATLAS results feature five separate searches for this elusive particle.

4 August 2016

Searching for new phenomena in final states with missing momentum and jets

The nature of dark matter remains one of the greatest mysteries in physics. While extraordinary, the Standard Model can not explain dark matter, whose existence is well established by cosmological measurements.

4 August 2016

The search for the dark side of the Universe

ATLAS scientists have just released a new publication with results based on an analysis of the early Run 2 data collected in 2015 using 13 TeV proton-proton collisions.

13 April 2016

Devouring dark matter theories

Most of the matter in the universe is made not of stuff we understand, but of invisible “dark matter” particles. We have yet to observe these mysterious particles on Earth, presumably because they interact so weakly with normal matter. The high energy collisions in the Large Hadron Collider provide our best current hope of making dark matter particles, and thus giving us a better understanding what most of the universe is made of.

24 August 2015

From ATLAS Around the World: Triggers (and dark) matter

To the best of our knowledge, it took the Universe about 13.798 billion years to allow funny looking condensates of mostly oxygen, carbon and hydrogen to ponder on their own existence. Some particularly curious specimens became scientists, founded CERN, dug several rings into the ground near Geneva, Switzerland, built the Large Hadron Collider, and also installed a handful of large detectors along the way.

27 July 2015

Looking at the Dark side of Matter

The search continues for dark matter, a new kind of matter that doesn’t emit or absorb light. It is assumed to account for the missing amount of mass in our Universe. The total mass in our Universe can be inferred from the observation of gravitational effects of stars in galaxies, and galaxies in clusters of galaxies. However the amount of mass calculated from the observed distribution of light is much less. It is proposed that dark matter makes up the discrepancy as it does not emit light.

19 February 2015

Dark Matters

The winter conference season is well under way, and what better way to fill my first blog post than with a report from one of the premier conferences in particle and astroparticle physics: the Rencontres de Moriond.

24 March 2014
24 March 2014

Moriond day 1: The outer limits

Not many trips take you to all ends of the world in one day, but that was nevertheless how it felt after the first talks at Moriond. Sunday and Monday have mainly featured presentations on neutrino and dark matter physics. Many of these experiments are placed in remote regions or deep under ground.

5 March 2012