Search for the Standard Model Scalar Boson with the ATLAS detector

TL;DR

This paper reports on the search for the Standard Model Higgs boson using ATLAS detector data at the LHC, excluding certain mass ranges and observing a modest excess near 126 GeV.

Contribution

First comprehensive search for the SM Higgs boson with ATLAS at 7 TeV, combining multiple decay channels over a wide mass range.

Findings

Excludes Higgs masses from 110 to 117.5 GeV, 118.5 to 122.5 GeV, and 129 to 539 GeV.

Observes a 2.5 sigma excess around 126 GeV.

Expected to exclude 120 to 555 GeV if no signal was present.

Abstract

The experimental results of the search for the Standard Model Higgs boson with the ATLAS detector at the Large Hadron Collider are reported, based on a dataset of pp collision data with an integrated luminosity of up to 4.9 fb^-1 at sqrt{s}=7 TeV. The search combines several Higgs boson decay channels in a wide range of Higgs boson masses from 110 GeV to 600 GeV. A Standard Model Higgs boson is excluded at the 95% confidence level in the mass ranges from 110.0 GeV to 117.5 GeV, 118.5 GeV to 122.5 GeV, and 129 GeV to 539 GeV, while the range from 120 GeV to 555 GeV is expected to be excluded in the absence of a signal. The most significant excess of events is observed around 126 GeV with a local significance of 2.5sigma. The global probability for such an excess to occur in the full searched mass range is approximately 30%.