%0 Journal Article
%T Constraints on the off-shell Higgs boson signal strength in the high-mass ZZ and WW final states with the ATLAS detector
%A ATLAS Collaboration (Aad, G. et al
%A Alvarez Piqueras, D.
%A Cabrera Urban, S.
%A Castillo Gimenez, V.
%A Costa, M. J.
%A Fernandez Martinez, P.
%A Ferrer, A.
%A Fiorini, L.
%A Fuster, J.
%A Garcia, C.
%A Garcia Navarro, J. E.
%A Gonzalez de la Hoz, S.
%A Hernandez Jimenez, Y.
%A Higon-Rodriguez, E.
%A Irles Quiles, A.
%A Jimenez Pena, J.
%A Kaci, M.
%A King, M.
%A Lacasta, C.
%A Lacuesta, V. R.
%A Marti-Garcia, S.
%A Mitsou, V. A.
%A Moles-Valls, R.
%A Oliver Garcia, E.
%A Pedraza Lopez, S.
%A Perez Garcia-Estañ, M. T.
%A Romero Adam, E.
%A Ros, E.
%A Salt, J.
%A Sanchez Martinez, V.
%A Soldevila, U.
%A Sanchez, J.
%A Torro Pastor, E.
%A Valero, A.
%A Valladolid Gallego, E.
%A Valls Ferrer, J. A.
%A Vos, M.
%J European Physical Journal C
%D 2015
%V 75
%N 7
%I Springer
%@ 1434-6044
%G English
%F ATLASCollaborationAad_etal2015
%O WOS:000361908300011
%O exported from refbase (https://references.ific.uv.es/refbase/show.php?record=2405), last updated on Thu, 22 Oct 2015 23:13:35 +0000
%X Measurements of the ZZ and WW final states in the mass range above the 2m(Z) and 2m(W) thresholds provide a unique opportunity to measure the off-shell coupling strength of the Higgs boson. This paper presents constraints on the off-shell Higgs boson event yields normalised to the Standard Model prediction (signal strength) in the ZZ -> 4l, ZZ -> 2l2 nu and WW -> e nu μnu final states. The result is based on pp collision data collected by the ATLAS experiment at the LHC, corresponding to an integrated luminosity of 20.3 fb(-1) at a collision energy of root s = 8 TeV. Using the CLs method, the observed 95 % confidence level (CL) upper limit on the off-shell signal strength is in the range 5.1-8.6, with an expected range of 6.7-11.0. In each case the range is determined by varying the unknown gg -> ZZ and gg -> WW background K-factor from higher-order quantum chromodynamics corrections between half and twice the value of the known signal K-factor. Assuming the relevant Higgs boson couplings are independent of the energy scale of the Higgs boson production, a combination with the on-shell measurements yields an observed (expected) 95 % CL upper limit on Gamma(H)/Gamma(SM)(H) in the range 4.5-7.5 (6.5-11.2) using the same variations of the background K-factor. Assuming that the unknown gg -> VV background K-factor is equal to the signal K-factor, this translates into an observed (expected) 95 % CL upper limit on the Higgs boson total width of 22.7 (33.0) MeV.
%R 10.1140/epjc/s10052-015-3542-2
%U http://arxiv.org/abs/1503.01060
%U https://doi.org/10.1140/epjc/s10052-015-3542-2
%P 335-34pp