Limits on the production of the standard model Higgs boson in pp collisions at TeV with the ATLAS detector

Dipartimento di Fisica E. Fermi, Università di Pisa, Pisa, Italy
European Physical Journal C (Impact Factor: 5.44). 06/2011; 71(9):1-30. DOI: 10.1140/epjc/s10052-011-1728-9

ABSTRACT A search for the Standard Model Higgs boson at the Large Hadron Collider (LHC) running at a centre-of-mass energy of 7TeV
is reported, based on a total integrated luminosity of up to 40pb−1 collected by the ATLAS detector in 2010. Several Higgs boson decay channels: H→γγ, H→ZZ
(∗)→ℓℓℓℓ, H→ZZ→ℓℓνν, H→ZZ→ℓℓqq, H→WW
(∗)→ℓνℓν and H→WW→ℓνqq (ℓis e, μ) are combined in a mass range from 110GeV to 600GeV. The highest sensitivity is achieved in the mass range between 160GeV
and 170GeV, 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 GeVto 185GeV.

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Available from: Ehud Duchovni, Sep 04, 2015
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