Rights statement: © CERN for the benefit of the ATLAS collaboration 2015. This article is published with open access at Springerlink.com EPJC is an open-access journal funded by SCOAP3 and licensed under CC BY 4.0
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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Search for the Standard Model Higgs boson produced in association with top quarks and decaying into bb in pp collisions at √s =8TeV with the ATLAS detector
AU - Barton, Adam
AU - Beattie, Michael
AU - Borissov, Guennadi
AU - Bouhova-Thacker, Eva
AU - Dearnaley, William
AU - Fox, Harald
AU - Grimm, Kathryn
AU - Henderson, Robert
AU - Hughes, Gareth
AU - Jones, Roger William Lewis
AU - Kartvelishvili, Vakhtang
AU - Long, Robin
AU - Love, Peter
AU - Maddocks, Harvey
AU - Skinner, Malcolm
AU - Smizanska, Maria
AU - Walder, James
AU - Wharton, Andy
AU - The ATLAS collaboration
AU - Muenstermann, Daniel
N1 - © CERN for the benefit of the ATLAS collaboration 2015. This article is published with open access at Springerlink.com EPJC is an open-access journal funded by SCOAP3 and licensed under CC BY 4.0 Date of acceptance not available
PY - 2015/7
Y1 - 2015/7
N2 - A search for the Standard Model Higgs boson produced in association with a top-quark pair, tt ¯ H , is presented. The analysis uses 20.3 fb−1 of pp collision data at s √ =8TeV , collected with the ATLAS detector at the Large Hadron Collider during 2012. The search is designed for the H→bb ¯ decay mode and uses events containing one or two electrons or muons. In order to improve the sensitivity of the search, events are categorised according to their jet and b-tagged jet multiplicities. A neural network is used to discriminate between signal and background events, the latter being dominated by tt ¯ +jets production. In the single-lepton channel, variables calculated using a matrix element method are included as inputs to the neural network to improve discrimination of the irreducible tt ¯ +bb ¯ background. No significant excess of events above the background expectation is found and an observed (expected) limit of 3.4 (2.2) times the Standard Model cross section is obtained at 95 % confidence level. The ratio of the measured tt ¯ H signal cross section to the Standard Model expectation is found to be μ=1.5±1.1 assuming a Higgs boson mass of 125GeV.
AB - A search for the Standard Model Higgs boson produced in association with a top-quark pair, tt ¯ H , is presented. The analysis uses 20.3 fb−1 of pp collision data at s √ =8TeV , collected with the ATLAS detector at the Large Hadron Collider during 2012. The search is designed for the H→bb ¯ decay mode and uses events containing one or two electrons or muons. In order to improve the sensitivity of the search, events are categorised according to their jet and b-tagged jet multiplicities. A neural network is used to discriminate between signal and background events, the latter being dominated by tt ¯ +jets production. In the single-lepton channel, variables calculated using a matrix element method are included as inputs to the neural network to improve discrimination of the irreducible tt ¯ +bb ¯ background. No significant excess of events above the background expectation is found and an observed (expected) limit of 3.4 (2.2) times the Standard Model cross section is obtained at 95 % confidence level. The ratio of the measured tt ¯ H signal cross section to the Standard Model expectation is found to be μ=1.5±1.1 assuming a Higgs boson mass of 125GeV.
U2 - 10.1140/epjc/s10052-015-3543-1
DO - 10.1140/epjc/s10052-015-3543-1
M3 - Journal article
VL - 75
JO - European Physical Journal C: Particles and Fields
JF - European Physical Journal C: Particles and Fields
SN - 1434-6044
M1 - 349
ER -