Search for the Standard Model Higgs boson decaying into bb¯ produced in association with top quarks decaying hadronically in pp collisions at √s = 8 TeV with the ATLAS detector

Summary, in English

A search for Higgs boson production in association with a pair of top quarks (tt¯ H) is performed, where the Higgs boson decays to bb¯, and both top quarks decay hadronically. The data used correspond to an integrated luminosity of 20.3 fb−1 of pp collisions at √s = 8 TeV collected with the ATLAS detector at the Large Hadron Collider. The search selects events with at least six energetic jets and uses a boosted decision tree algorithm to discriminate between signal and Standard Model background. The dominant multijet background is estimated using a dedicated data-driven technique. For a Higgs boson mass of 125 GeV, an upper limit of 6.4 (5.4) times the Standard Model cross section is observed (expected) at 95% confidence level. The best-fit value for the signal strength is μ = 1.6 ± 2.6 times the Standard Model expectation for mH = 125 GeV. Combining all tt¯ H searches carried out by ATLAS at √s = 8 and 7 TeV, an observed (expected) upper limit of 3.1 (1.4) times the Standard Model expectation is obtained at 95% confidence level, with a signal strength μ = 1.7 ± 0.8. © 2016, The Author(s).

• Author: G Aad; B. Abbott; J Abdallah; B Abeloos; R Aben; M Abolins; Torsten Åkesson; Simona Bocchetta; LENE BRYNGEMARK; Caterina Doglioni; Anders Floderus; Anthony Hawkins; Vincent Hedberg; Göran Jarlskog; Else Lytken; Ulf Mjörnmark; Oxana Smirnova; Oleksandr Viazlo
• Department/s: Particle and nuclear physics; eSSENCE: The e-Science Collaboration
• Publishing year: 2016
• Language: English
• Publication/Series: Journal of High Energy Physics
• Volume: 2016
• Issue: 5
• Links: http://dx.doi.org/10.1007/JHEP05(2016)160
• Document type: Journal article
• Publisher: Springer
• Topic: Subatomic Physics
• Keywords: Hadron-Hadron scattering (experiments)
• Status: Published
• ISBN/ISSN/Other: ISSN: 1029-8479