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

A search for the Standard Model Higgs boson with the ATLAS experiment at the LHC is presented. The pp collisions datasets correspond to an integrated luminosity of up to 4.9fb−1 collected at s=7TeV in 2011, and up to 5.9fb−1 collected at s=8TeV in 2012. Searches for H→γγ, H→ZZ(⁎), H→WW(⁎), H→bb¯ and H→τ+τ− have been performed on the 2011 data, while H→γγ and H→ZZ(⁎)→4l have been updated using both 2011 and 2012 data. The Standard Model Higgs boson has been excluded at 95% confidence level for masses in the range of 110 to 122.6 GeV and 129.7 to 558 GeV. An excess of events has been observed for a Higgs boson mass hypothesis near 126.5 GeV with a local significance of 5.0σ.