Scientists working on the ATLAS and CMS experiments at CERN announced the observation of a new particle with a mass of about 125 gigaelectronvolts, consistent with the Higgs boson predicted in 1964.
The particle is associated with the field that gives mass to elementary particles, completing the standard model of particle physics. Both experiments reported results at the five-sigma level of statistical significance, the conventional threshold for a discovery.
Peter Higgs and François Englert, who developed the theory, were awarded the Nobel Prize in Physics the following year.
