A search for the standard model Higgs boson decaying to a W-boson pair at the LHC is reported. The event sample corresponds to an integrated luminosity of 4.9 fb −1 and 19.4 fb −1 collected with the CMS detector in pp collisions at √ s = 7 and 8 TeV, respectively. The Higgs boson candidates are selected in events with two or three charged leptons. An excess of events above background is observed, consistent with the expectation from the standard model Higgs boson with a mass of around 125 GeV. The probability to observe an excess equal or larger than the one seen, under the background-only hypothesis, corresponds to a significance of 4.3 standard deviations for m H = 125.6 GeV. The observed signal cross section times the branching fraction to WW for m H = 125.6 GeV is 0.72 +0.20 −0.18 times the standard model expectation. The spin-parity J P = 0 + hypothesis is favored against a narrow resonance with J P = 2 + or J P = 0 − that decays to a W-boson pair. This result provides strong evidence for a Higgs-like boson decaying to a W-boson pair. Finding such a signal in the complex environment of a hadron collider is not straightforward. A complete reconstruction of all the final-state particles is not possible because of the presence of neutrinos which are not directly detected. Kinematic observables such as the opening angle between the two charged leptons in the transverse plane, the dilepton mass, and the transverse mass of the system of the two leptons and the neutrinos, can be used to distinguish not only the Higgs boson signal from background processes with similar signature [17,18], but also between the SM Higgs boson hypothesis and other narrow exotic resonances with different spin or parity. Phenomenological studies of the amplitudes for the decay of a Higgs or an exotic boson into the WW final state demonstrate a good sensitivity to distinguish between the SM Higgs boson hypothesis (spin-parity 0 + ) and a spin-2 resonance, which couples to the bosons through minimal couplings, referred to as 2 + min [19]. Some sensitivity has also been shown with this final state to distinguish between the 0 + and the pseudoscalar 0 − boson hypotheses. Keywords: Hadron-Hadron Scattering, Higgs physics-1 - JHEP01(2014)096Searches for the SM Higgs boson in the H → WW final state at the LHC have previously been performed using data at √ s = 7 TeV by CMS [20][21][22], excluding the presence of the SM Higgs boson at the 95% CL in the mass range 129-270 GeV, and by ATLAS [23], excluding the mass range 133-261 GeV. Using their full dataset at 7 and 8 TeV, ATLAS have reported a H → WW signal with a statistical significance of 3.8 standard deviations [24] as well as evidence for the spin zero nature of the Higgs boson [25].This paper reports a measurement of the production and properties of the Higgs boson in the WW decay channel using the entire dataset collected by the CMS experiment during the 2011 and 2012 LHC running period. Various production modes, using events with two or three charged leptons ( ), electrons o...

Properties of the Higgs boson are measured in the H → ZZ → 4 ( = e, µ) decay channel. A data sample of proton-proton collisions at √ s = 13 TeV, collected with the CMS detector at the LHC and corresponding to an integrated luminosity of 35.9 fb −1 is used. The signal strength modifier µ, defined as the ratio of the observed Higgs boson rate in the H → ZZ → 4 decay channel to the standard model expectation, is measured to be µ = 1.05 +0.19−0.17 at m H = 125.09 GeV, the combined ATLAS and CMS measurement of the Higgs boson mass. The signal strength modifiers for the individual Higgs boson production modes are also measured. The cross section in the fiducial phase space defined by the requirements on lepton kinematics and event topology is measured to be 2.92−0.24 (syst) fb, which is compatible with the standard model prediction of 2.76 ± 0.14 fb. Differential cross sections are reported as a function of the transverse momentum of the Higgs boson, the number of associated jets, and the transverse momentum of the leading associated jet. The Higgs boson mass is measured to be m H = 125.26 ± 0.21 GeV and the width is constrained using the on-shell invariant mass distribution to be Γ H < 1.10 GeV, at 95% confidence level. The H → ZZ → 4 decay channel ( = e, µ) has a large signal-to-background ratio, and the precise reconstruction of the final-state decay products allows the complete determination of the kinematics of the Higgs boson. This makes it one of the most important channels to measure the properties of the Higgs boson. Measurements performed by the ATLAS and CMS Collaborations using this decay channel with the LHC Run 1 data include the determination of the mass and spin-parity of the boson [14][15][16][17][18], its width [19][20][21], the fiducial cross sections [22, 23], and the tensor structure of its interaction with a pair of neutral gauge bosons [16, 18, 20]. KeywordsIn this paper measurements of properties of the Higgs boson decaying into the fourlepton final state in proton-proton (pp) collisions at √ s = 13 TeV are presented. Events are classified into categories optimized with respect to those used in ref.[14] to provide increased sensitivity to subleading production modes of the Higgs boson such as vector boson fusion (VBF) and associated production with a vector boson (WH, ZH) or top quark pair (ttH). The signal strength modifier, defined as the ratio of the measured Higgs boson rate in the H → ZZ → 4 decay channel to the SM expectation, is measured. The signal strength modifiers for the individual Higgs boson production modes are constrained. In addition, cross section measurements and dedicated measurements of the mass and width of the Higgs boson are performed. This paper is structured as follows: the apparatus and the data samples are described in section 2 and section 3. Section 4 summarizes the event reconstruction and selection. Kinematic discriminants and event categorization are discussed in section 5 and section 6. The background estimation and the signal modelling are reported i...

A search is presented for additional neutral Higgs bosons in the ττ final state in proton-proton collisions at the LHC. The search is performed in the context of the minimal supersymmetric extension of the standard model (MSSM), using the data collected with the CMS detector in 2016 at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9 fb −1 . To enhance the sensitivity to neutral MSSM Higgs bosons, the search includes production of the Higgs boson in association with b quarks. No significant deviation above the expected background is observed. Model-independent limits at 95% confidence level (CL) are set on the product of the branching fraction for the decay into τ leptons and the cross section for the production via gluon fusion or in association with b quarks. These limits range from 18 pb at 90 GeV to 3.5 fb at 3.2 TeV for gluon fusion and from 15 pb (at 90 GeV) to 2.5 fb (at 3.2 TeV) for production in association with b quarks, assuming a narrow width resonance. In the m mod+ h scenario these limits translate into a 95% CL exclusion of tan β > 6 for neutral Higgs boson masses below 250 GeV, where tan β is the ratio of the vacuum expectation values of the neutral components of the two Higgs doublets. The 95% CL exclusion contour reaches 1.6 TeV for tan β = 60.

Measurements of the normalized rapidity (y) and transverse-momentum (q T ) distributions of Drell-Yan muon and electron pairs in the Z-boson mass region (60 < M '' < 120 GeV) are reported. The results are obtained using a data sample of proton-proton collisions at a center-of-mass energy of 7 TeV, collected by the CMS experiment at the Large Hadron Collider (LHC), corresponding to an integrated luminosity of 36 pb À1 . The distributions are measured over the ranges jyj < 3:5 and q T < 600 GeV and compared with quantum chromodynamics (QCD) calculations using recent parton distribution functions to model the momenta of the quarks and gluons in the protons. Overall agreement is observed between the models and data for the rapidity distribution, while no single model describes the Z transverse-momentum distribution over the full range.

No abstract