In Brief
The observations support a fundamental theory of particle physics, according to a paper published today in the journal Nature.
  • Particle decay occurs when elementary particles spontaneously transform into other elementary particles. In the LHC experiments, protons collided at high energy to create 1 trillion particles known as neutral B mesons, some of which then decayed into pairs of oppositely charged muons — heavier “cousins” of electrons. 
  • The decay of one type of B mesons, known as “strange” mesons, occurred at the same frequency predicted by the Standard Model (about four in 1 billion), with a confidence level high enough to qualify as a discovery. The decay of non-strange B mesons also aligned with Standard Model predictions (about one in 10 billion), albeit at a lower confidence level (99.7 percent).
  • The good news for CERN and other physicists is that more data is on the way. Last month, the LHC restarted after a two-year hiatus for maintenance and repairs, and its proton collisions are expected to carry twice as much energy as they did at its debut. That will result in more precise observations, experts say, and, perhaps, a blueprint to explain the vast parts of the universe that the Standard Model cannot.