The activity Particle Physics aims to extend the frontiers of physics knowledge using the advanced technology of the world's largest and highest energy particle accelerator, the LHC. The Norwegian contributions within this field are mainly focused around the largest volume detector ever constructed at a particle collider, ATLAS. Particle physics studies the most fundamental constituents of matter called fundamental particles and tests the Standard Model's predictions and limits. The activity also works closely with theoretical particle and astroparticle physicists, creating synergies in interpreting results and widening the scope for new physics searches. Further, there are collaborations with others, such as NorduGrid, USIT, NeIC, Uninett Sigma 2, SDI, and SINTEF.
The LHC and the ATLAS experiment have so far been hugely successful. The discovery of the Higgs particle and the painstaking search for new physics in all possible corners of the data set are the highlights so far. Norwegian scientists have contributed to the ATLAS detector's operation and collected more than 140 fb-1 of proton-proton collision data at 13 TeV energy. The physics publications cover extensive searches for new physics phenomena and Standard Model processes (Higgs boson and Bottom quark physics). There have been measured fermionic and bosonic Higgs decay channels, search for supersymmetric particles involving light leptons and taus, and for exotic particles in the di-lepton and lepton-neutrino mass spectra. The activity also complemented the search for dark matter within supersymmetry by studying mono-Higgs, mono-Z and mono-Z’ processes. The ambitious remaining physics programme may shed light on the nature of dark matter and the gravitational force's behaviour at the microscopic scale.