Search for the associated production of the Higgs boson with a top quark pair in multilepton final states with the ATLAS detector

Barton, Adam and Beattie, Michael and Borissov, Guennadi and Bouhova-Thacker, Evelina Vassileva and Dearnaley, William and Fox, Harald and Grimm, Kathryn Ann Tschann and Henderson, Robert Charles William and Hughes, Gareth and Jones, Roger William Lewis and Kartvelishvili, Vakhtang and Long, Robin Eamonn and Love, Peter Allan and Maddocks, Harvey and Skinner, Malcolm and Smizanska, Maria and Walder, James William and Wharton, Andy (2015) Search for the associated production of the Higgs boson with a top quark pair in multilepton final states with the ATLAS detector. Physics Letters B, 749. pp. 519-541. ISSN 0370-2693

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Abstract

A search for the associated production of the Higgs boson with a top quark pair is performed in multilepton final states using 20.3 fb−1 of proton–proton collision data recorded by the ATLAS experiment at View the MathML source at the Large Hadron Collider. Five final states, targeting the decays H→WW*, ττ , and ZZ*, are examined for the presence of the Standard Model (SM) Higgs boson: two same-charge light leptons (e or μ) without a hadronically decaying τ lepton; three light leptons; two same-charge light leptons with a hadronically decaying τ lepton; four light leptons; and one light lepton and two hadronically decaying τ leptons. No significant excess of events is observed above the background expectation. The best fit for the View the MathML source production cross section, assuming a Higgs boson mass of 125 GeV, is View the MathML source times the SM expectation, and the observed (expected) upper limit at the 95% confidence level is 4.7 (2.4) times the SM rate. The p-value for compatibility with the background-only hypothesis is 1.8σ; the expectation in the presence of a Standard Model signal is 0.9σ.

Item Type:
Journal Article
Journal or Publication Title:
Physics Letters B
Uncontrolled Keywords:
/dk/atira/pure/subjectarea/asjc/3100/3106
Subjects:
ID Code:
78028
Deposited By:
Deposited On:
28 Jan 2016 10:24
Refereed?:
Yes
Published?:
Published
Last Modified:
05 Apr 2020 03:47