Observation and measurement of Higgs boson decays to WW∗ with the ATLAS detector

Allbrooke, B M M, Asquith, L, Cerri, A, Chavez Barajas, C A, De Santo, A, Salvatore, F, Santoyo Castillo, I, Suruliz, K, Sutton, M R, Vivarelli, I and The ATLAS Collaboration, et al. (2015) Observation and measurement of Higgs boson decays to WW∗ with the ATLAS detector. Physical Review D (PRD), 92 (01). ISSN 2470-0010

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Abstract

We report the observation of Higgs boson decays to WW∗ based on an excess over background of 6.1 standard deviations in the dilepton final state, where the Standard Model expectation is 5.8 standard deviations. Evidence for the vector-boson fusion (VBF) production process is obtained with a significance of 3.2 standard deviations. The results are obtained from a data sample corresponding to an integrated luminosity of 25  fb−1 from √s=7 and 8 TeV pp collisions recorded by the ATLAS detector at the LHC. For a Higgs boson mass of 125.36 GeV, the ratio of the measured value to the expected value of the total production cross section times branching fraction is 1.09 +0.16−0.15(stat) +0.17−0.14(syst). The corresponding ratios for the gluon fusion and vector-boson fusion production mechanisms are 1.02±0.19(stat) +0.22−0.18(syst) and 1.27 +0.44−0.40(stat) +0.30−0.21(syst), respectively. At √s=8  TeV, the total production cross sections are measured to be σ(gg→H→WW∗)=4.6±0.9(stat) +0.8−0.7(syst)  pb and σ(VBFH→WW∗)=0.51 +0.17−0.15(stat) +0.13−0.08(syst)  pb. The fiducial cross section is determined for the gluon-fusion process in exclusive final states with zero or one associated jet.

Item Type: Article
Schools and Departments: School of Mathematical and Physical Sciences > Physics and Astronomy
Research Centres and Groups: Experimental Particle Physics Research Group
Subjects: Q Science > QC Physics
Depositing User: Billy Wichaidit
Date Deposited: 28 Apr 2017 09:13
Last Modified: 28 Apr 2017 19:20
URI: http://sro.sussex.ac.uk/id/eprint/67554

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Project NameSussex Project NumberFunderFunder Ref
ATLASG0275STFC-SCIENCE AND TECHNOLOGY FACILITIES COUNCILST/I006048/1