Partial-symmetries of weak interactions

Measurement of WW + WZ production cross section and study of the dijet mass spectrum in the ℓν + jets final state at CDF

“…A big success of the SM is the unification of the electromagnetic and the weak forces into the so called electroweak force [6]. The idea of the unification is to combine both interactions into one single theoretical framework, in which they would appear as two manifestations of the same fundamental force.…”

“…6 The radiation length X0 describes the characteristic amount of matter transversed, for highenergy electrons to lose all but 1/e of its energy by bremsstrahlung, which is equivalent to 7 9 of the length of the mean free path for pair e + e − production of high-energy photons. The average energy loss due to bremsstrahlung for an electron of energy E is related to the radiation length by dE dx brems = − E X 0 .…”

Measurement of tau lepton branching fractions

“…Within this theory there are electroweak interactions [5,6,7] mediated by the massless photon and the massive W+, W-, and ZO bosons, . and strong interactions mediated by eight types of gluons.…”

Observation of an excess of events in the Higgs boson search in ATLAS

“…In the Standard Model (SM) [2][3][4], electroweak symmetry breaking is provided by the Higgs mechanism, resulting in a new particle referred to as the Higgs boson [5][6][7][8][9][10]. While the production cross section and branching ratios can be determined for a given Higgs boson mass, m H , the actual value of the Higgs boson mass is not known and the search must be performed over a wide range of Higgs boson masses.…”