Study of (W/Z)H production and Higgs boson couplings using H→ W W ∗ decays with the ATLAS detector

Barton, Adam 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) Study of (W/Z)H production and Higgs boson couplings using H→ W W ∗ decays with the ATLAS detector. Journal of High Energy Physics (8). ISSN 1029-8479

[img]
Preview
PDF (art%3A10.1007%2FJHEP08%282015%29137)
art_3A10.1007_2FJHEP08_282015_29137.pdf - Published Version
Available under License Creative Commons Attribution.

Download (1MB)

Abstract

A search for Higgs boson production in association with a W or Z boson, in the H→ W W ∗ decay channel, is performed with a data sample collected with the ATLAS detector at the LHC in proton-proton collisions at centre-of-mass energies s√=7 TeV and 8 TeV, corresponding to integrated luminosities of 4.5 fb−1 and 20.3 fb−1, respectively. The WH production mode is studied in two-lepton and three-lepton final states, while two- lepton and four-lepton final states are used to search for the ZH production mode. The observed significance, for the combined W H and ZH production, is 2.5 standard deviations while a significance of 0.9 standard deviations is expected in the Standard Model Higgs boson hypothesis. The ratio of the combined W H and ZH signal yield to the Standard Model expectation, μ V H , is found to be μ V H  = 3.0 − 1.1 + 1.3 (stat.) − 0.7 + 1.0 (sys.) for the Higgs boson mass of 125.36 GeV. The W H and ZH production modes are also combined with the gluon fusion and vector boson fusion production modes studied in the H → W W ∗ → ℓνℓν decay channel, resulting in an overall observed significance of 6.5 standard deviations and μ ggF + VBF + VH = 1. 16 − 0.15 + 0.16 (stat.) − 0.15 + 0.18 (sys.). The results are interpreted in terms of scaling factors of the Higgs boson couplings to vector bosons (κ V ) and fermions (κ F ); the combined results are: |κ V | = 1.06 − 0.10 + 0.10 , |κ F | = 0. 85 − 0.20 + 0.26 .

Item Type: Journal Article
Journal or Publication Title: Journal of High Energy Physics
Uncontrolled Keywords: /dk/atira/pure/subjectarea/asjc/3100/3106
Subjects:
Departments: Faculty of Science and Technology > Physics
ID Code: 77848
Deposited By: ep_importer_pure
Deposited On: 20 Jan 2016 16:40
Refereed?: Yes
Published?: Published
Last Modified: 26 Feb 2020 02:58
URI: https://eprints.lancs.ac.uk/id/eprint/77848

Actions (login required)

View Item View Item