Constraints on the Higgs boson width from off-shell production and decay to Z-boson pairs

Abstract

Constraints are presented on the total width of the recently discovered Higgs boson, Gamma[H], using its relative on-shell and off-shell production and decay rates to a pair of Z bosons, where one Z boson decays to an electron or muon pair, and the other to an electron, muon, or neutrino pair. The analysis is based on the data collected by the CMS experiment at the LHC in 2011 and 2012, corresponding to integrated luminosities of 5.1 inverse femtobarns at a centre-of-mass energy sqrt(s) = 7 TeV and 19.7 inverse femtobarns at sqrt(s) = 8 TeV. A simultaneous maximum likelihood fit to the measured kinematic distributions near the resonance peak and above the Z-boson pair production threshold leads to an upper limit on the Higgs boson width of Gamma[H] < 22 MeV at a 95% confidence level, which is 5.4 times the expected value in the standard model at the measured mass

Scalar simplified models for dark matter

“…This constrains the Higgs width to be Γ h < 17.4 MeV [158,159]. However, as with the invisible Higgs decay measurement, this interference effect does make some assumptions about the production mechanism of the Higgs [118,160].…”

Weak interactions in top-quark pair production at hadron colliders: An Update

“…The relevance of such a limit on g Y can be illustrated by comparing with the limits on the Higgs couplings as suggested in Refs. [64,65] and presented recently by both CMS [66] and ATLAS [67] collaborations. In these papers it has been demonstrated that a universal rescaling g SM → κg SM combined with an increase of the Higgs width by a factor κ 4 (e.g.…”

“…In these papers it has been demonstrated that a universal rescaling g SM → κg SM combined with an increase of the Higgs width by a factor κ 4 (e.g. through some presently invisible mode) can be excluded for values of κ 4 exceeding 7.7 [67] or even 5.4 [66]. Such a rescaling would also involve the top quark Yukawa coupling, and it remains to be seen, if similar limits can be obtained from analysis of the top quark threshold behaviour.…”

QCD radiative corrections for h→bb¯ in the standard model dimension-6 effective field theory

“…An extraction of the total width from experimental data (under minimal assumptions) through interference effects [12][13][14][15][16] is possible, and additional information can also be gained by including LEP data [17]. However, the current constraint from this technique is approximately Γ h < 5Γ SM h [18,19]. A precise model independent measurement of both these quantities requires input from a dedicated "Higgs machine".…”