Limits on the production of the standard model Higgs boson in pp collisions at root s=7 TeV with the ATLAS detector
Abstract
A search for the Standard Model Higgs boson at the Large Hadron Collider (LHC) running at a centre-of-mass energy of 7 TeV is reported, based on a total integrated luminosity of up to 40 pb(-1) collected by the ATLAS detector in 2010. Several Higgs boson decay channels: H -} gamma gamma, H -} ZZ(()*()) -} llll, H -} ZZ -} LL nu nu, H -} ZZ -} llqq, H -} WW(()*()) -} l nu l nu and H -} WW -} l nu qq (l is e, mu) are combined in a mass range from 110 GeV to 600 GeV.
The highest sensitivity is achieved in the mass range between 160 GeV and 170 GeV, where the expected 95% CL exclusion sensitivity is at Higgs boson production cross sections 2.3 times the Standard Model prediction. Upper limits on the cross section for its production are determined.
Models with a fourth generation of heavy leptons and quarks with Standard Model-like couplings to the Higgs boson are also investigated and are excluded at 95% CL for a Higgs boson mass in the range from 140 GeV to 185 GeV.