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

Allison, Lee and Barton, Adam and Beattie, Michael and Borissov, Guennadi and Bouhova-Thacker, Eva and Chilingarov, Alexandre and Dearnaley, William and Fox, Harald and Grimm, Kathryn and Henderson, Robert and Hughes, Gareth and Jones, Roger William Lewis and Kartvelishvili, Vakhtang and Long, Robin and Love, Peter and Maddocks, Harvey and Smizanska, Maria and Walder, James (2015) Observation and measurement of Higgs boson decays to WW∗ with the ATLAS detector. Physical Review D, 92 (1). ISSN 1550-7998

[img]
Preview
PDF (PhysRevD.92)
PhysRevD.92.pdf - Published Version
Available under License Creative Commons Attribution.

Download (5MB)

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(VBF  H→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:
Journal Article
Journal or Publication Title:
Physical Review D
Additional Information:
This article is available under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. © 2015 CERN, for the ATLAS Collaboration
ID Code:
75591
Deposited By:
Deposited On:
11 Sep 2015 15:25
Refereed?:
Yes
Published?:
Published
Last Modified:
12 Jul 2020 05:14