Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC

The ATLAS collaboration reported the first observation of a new boson at approximately 125-126 GeV with local significance 5.9 sigma, combining H->ZZ->4l, H->gamma-gamma, and H->WW decay channels. The simultaneous combination of independent channels via a profile likelihood with profiled nuisance parameters for systematics was the key statistical framework. Signal strength measurements consistent with SM predictions were reported across all channels simultaneously.