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

A search for the Standard Model Higgs boson in proton–proton collisions with the ATLAS detector at the LHC is presented. The datasets used correspond to integrated luminosities of approximately 4.8 fb-1 collected at vs = 7 TeV in 2011 and 5.8 fb-1 at vs = 8 TeV in 2012. Individual searches in the channels H?ZZ(*)?4l, H??? and H?WW(*)?e?µ?inthe8TeVdataarecombinedwithpreviously published results of searches for H ? Z Z(*), W W (*), bb ¯ and t+t- in the 7 TeV data and results from improved analyses of the H ? Z Z (*) ? 4l and H ? ? ? channels in the 7 TeV data. Clear evidence for the production of a neutral boson with a measured mass of 126.0±0.4 (stat)±0.4 (sys) GeV is presented. This observation, which has a significance of 5.9 standard deviations, corresponding to a background fluctuation probability of 1.7×10-9, is compatible with the production and decay of the Standard Model Higgs boson.