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Questions about Standard Model

Short answers, pulled from the story.

When was the Standard Model term first used in print?

The term Standard Model appeared in print when Abraham Pais and Sam Treiman used it in 1975. Steven Weinberg claimed he chose the phrase out of modesty during a talk in Aix-en-Provence in France back in 1973.

What particles make up the twelve fermions in the Standard Model?

The Standard Model includes six quarks known as up, down, charm, strange, top, and bottom. It also contains six leptons consisting of electron, electron neutrino, muon, muon neutrino, tau, and tau neutrino.

Which bosons mediate the four fundamental forces in the Standard Model?

Photons mediate electromagnetic force between charged particles while gluons mediate strong interactions binding quarks together. W and Z bosons mediate weak interactions responsible for radioactivity and the Higgs boson is a massive scalar particle with spin zero discovered experimentally in 2012.

How many free parameters does the Standard Model require from experimental data?

Dynamics depend on nineteen parameters whose values come from experiment including electron mass measuring 0.511 MeV and muon mass reaching 105.7 MeV. Top quark mass sits around 173.5 GeV on shell scheme while the Higgs vacuum expectation value sets electroweak physics scale near 246 GeV.

When was the Higgs boson officially confirmed by experiments at CERN?

Two independent experiments reported finding a new particle with mass about 125 GeV on the 4th of July 2012. Confirmation arrived the 13th of March 2013 that this was indeed the searched-for Higgs boson.