A Massive Particle Consistent with the Standard Model Higgs Boson observed with the ATLAS Detector at the Large Hadron Collider

The standard model of particle physics describes how elementary particles and a set of forces between them lead to all matter and most higher interactions, thereby providing a basis for understanding much of physics and chemistry. A key prediction of the standard model—that the universe is pervaded by a field that conveys mass—was tested and confirmed this year with the discovery of a particle associated with that fi eld: the Higgs boson. Two separate, complex detectors housed in the largest and most energetic particle accelerator, the Large Hadron Collider (LHC) at CERN near Geneva, Switzerland, identifi ed the characteristic decay products of the Higgs, allowing reconstruction of its mass. These experiments and this discovery were made possible by decades of cutting-edge, publicly supported science, engineering, and construction, and a longterm effort by the physics community worldwide. In three articles in this issue, the researchers explain their results and the developments that led to the detection. The first presents the history of the search for the Higgs and the experimentalapproach, and summarizes the results. This is followed by a paper from each of the two detector teams describing their experiments and results in more detail. These papers aim to provide an accessible overview of the two research papers published this summer in Physics Letters B, which are the primary references. We hope that this package and the accompanying glossary give broad access to this discovery that is fundamental to understanding our universe.