The discovery and measurements of a Higgs boson.

In July 2012, the ATLAS and CMS collaborations at CERN's Large Hadron Collider announced the discovery of a Higgs-like boson, a new heavy particle at a mass more than 130 times the mass of a proton. Since then, further data have revealed its properties to be strikingly similar to those of the Standard Model Higgs boson, a particle expected from the mechanism introduced almost 50 years ago by six theoreticians including British physicists Peter Higgs from Edinburgh University and Tom Kibble from Imperial College London. The discovery is the culmination of a truly remarkable scientific journey and undoubtedly the most significant scientific discovery of the twenty-first century so far. Its experimental confirmation turned out to be a monumental task requiring the creation of an accelerator and experiments of unprecedented capability and complexity, designed to discern the signatures that correspond to the Higgs boson. Thousands of scientists and engineers, in each of the ATLAS and CMS teams, came together from all four corners of the world to make this massive discovery possible.

Beyond the standard model of particle physics.

The Large Hadron Collider (LHC) at CERN and its experiments were conceived to tackle open questions in particle physics. The mechanism of the generation of mass of fundamental particles has been elucidated with the discovery of the Higgs boson. It is clear that the standard model is not the final theory. The open questions still awaiting clues or answers, from the LHC and other experiments, include: What is the composition of dark matter and of dark energy? Why is there more matter than anti-matter? Are there more space dimensions than the familiar three? What is the path to the unification of all the fundamental forces? This talk will discuss the status of, and prospects for, the search for new particles, symmetries and forces in order to address the open questions.This article is part of the themed issue 'Unifying physics and technology in light of Maxwell's equations'.

Physics requirements for the design of the ATLAS and CMS experiments at the Large Hadron Collider.

The ATLAS and CMS experiments at the CERN Large Hadron Collider are discovery experiments. Thus, the aim was to make them sensitive to the widest possible range of new physics. New physics is likely to reveal itself in addressing questions such as: how do particles acquire mass; what is the particle responsible for dark matter; what is the path towards unification; do we live in a world with more space-time dimensions than the familiar four? The detection of the Higgs boson, conjectured to give mass to particles, was chosen as a benchmark to test the performance of the proposed experiment designs. Higgs production is one of the most demanding hypothesized processes in terms of required detector resolution and background discrimination. ATLAS and CMS feature full coverage, 4π-detectors to measure precisely the energies, directions and identity of all the particles produced in proton-proton collisions. Realizing this goal has required the collaborative efforts of enormous teams of people from around the world.

Journey in the search for the Higgs boson: the ATLAS and CMS experiments at the Large Hadron Collider.

The search for the standard model Higgs boson at the Large Hadron Collider (LHC) started more than two decades ago. Much innovation was required and diverse challenges had to be overcome during the conception and construction of the LHC and its experiments. The ATLAS and CMS Collaboration experiments at the LHC have discovered a heavy boson that could complete the standard model of particle physics.