Scientists at the Large Hadron Collider at CERN, Switzerland, have announced that they have discovered a new particle with properties which would be consistent with the Higgs boson. Although 2 separate teams of scientists had independently confirmed the finding, both teams agree that further analysis is needed before the new particle can be conclusively called the Higgs boson.
What is the Higgs boson?
The current understanding of physics uses the Standard Model to explain particle interactions. However, prior to the 1970s, the Standard Model could not explain why some elementary particles had mass.
The simplest solution to this dilemma was a theoretical Higgs field, which would interact with elementary particles to give them mass. If this theory was true, a Higgs boson would also have to exist as a counterpart to this field. The field could not be directly measured, but a particle accelerator which was powerful enough should be able to create it. It would decay again almost instantly, but if it could be created at all, the traces of its decay could be recorded.
A Higgs boson created from a proton-proton collision would decay into 2 jets of hadrons and 2 electrons. However, other events could create the same reaction. Scientists have to be careful to eliminate other possibilities, including the possibility that the decay pattern was created by chance.
The Higgs boson is sometimes nicknamed the God particle because its existence will answer some questions about the Standard Model. It is also nicknamed the God particle for similar reasons as the ivory-billed woodpecker is nicknamed the Lord God bird. Finding the Higgs particle will be the find of a lifetime.
The search
The quest for the Higgs boson involved 2 independent groups of scientists using 2 different but complementary methods: the Compact Muon Solenoid (CMS) experiment and the A Toroidal LHC Apparatus (ATLAS) experiment. By late 2011, these 2 groups had narrowed the energy range of possible Higgs boson detection to around 125 GeV.
On July 4, 2012, both the CMS and ATLAS teams announced initial findings which would be consistent with a Standard Model Higgs boson. Stephen Hawking lost a $100 bet over the finding.
However, the current evidence could also be consistent with an unexpected form of Higgs boson. If this turns out to be the case, it could require a complete overhaul of the current version of the Standard Model. Back to the drawing board.