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Measurement of the ${{\mathrm{W} }^{+} }\mathrm{W}^{-} $ cross section in pp collisions at $\sqrt{s} =$ 8 TeV and limits on anomalous gauge couplings

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Eur.Phys.J. C76 (2016) 401, 2016.
Inspire Record 1382594 DOI 10.17182/hepdata.79411

A measurement of the W boson pair production cross section in proton-proton collisions at $\sqrt{s} = 8$  TeV is presented. The data collected with the CMS detector at the LHC correspond to an integrated luminosity of 19.4 $\,\text {fb}^\text {-1}$ . The ${{\mathrm{W} }^{+} }\mathrm{W}^{-} $ candidates are selected from events with two charged leptons, electrons or muons, and large missing transverse energy. The measured ${{\mathrm{W} }^{+} }\mathrm{W}^{-} $ cross section is $60.1\pm 0.9\,\text {(stat)} \pm 3.2\,\text {(exp)} \pm 3.1\,\text {(theo)} \pm 1.6\,\text {(lumi)} \text {\,pb} = 60.1\pm 4.8\text {\,pb} $ , consistent with the standard model prediction. The ${{\mathrm{W} }^{+} }\mathrm{W}^{-} $ cross sections are also measured in two different fiducial phase space regions. The normalized differential cross section is measured as a function of kinematic variables of the final-state charged leptons and compared with several perturbative QCD predictions. Limits on anomalous gauge couplings associated with dimension-six operators are also given in the framework of an effective field theory. The corresponding 95 % confidence level intervals are $-5.7< c_{\mathrm {WWW}}/\Lambda ^2 < 5.9\,\mathrm{TeV}^{-2}$ , $-11.4< c_{\mathrm {W}}/\Lambda ^2 < 5.4\,\mathrm{TeV}^{-2}$ , $-29.2< c_{\mathrm {B}}/\Lambda ^2 < 23.9\,\mathrm{TeV}^{-2}$ , in the HISZ basis.

9 data tables

The W+W- production cross section combining the four event categories (different-flavor and same-flavor in the 0-jet and 1-jet bin separately) by performing a profile likelihood fit to the data.

The W+W- production cross section in fiducial regions defined by requiring no jets at particle level with jet pT thresholds as listed.

The W+W- production cross section in fiducial regions defined by requiring zero jets at particle level with varying jet pT thresholds and requiring prompt leptons with pT > 20 GeV and abs(eta) < 2.5, before final-state radiation.

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Search for a Higgs Boson in the Mass Range from 145 to 1000 GeV Decaying to a Pair of W or Z Bosons

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
JHEP 1510 (2015) 144, 2015.
Inspire Record 1357982 DOI 10.17182/hepdata.70736

A search for a heavy Higgs boson in the $\mathrm{H \to WW}$ and $\mathrm{H \to ZZ}$ decay channels is reported. The search is based upon proton-proton collision data samples corresponding to an integrated luminosity of up to 5.1 fb$^{-1}$ at $\sqrt{s}$ = 7 TeV and up to 19.7 fb$^{-1}$ at $\sqrt{s}$ = 8 TeV, recorded by the CMS experiment at the CERN LHC. Several final states of the $\mathrm{H \to WW}$ and $\mathrm{H \to ZZ}$ decays are analyzed. The combined upper limit at the 95% confidence level on the product of the cross section and branching fraction exclude a Higgs boson with standard model-like couplings and decays in the $m_{\mathrm{H}}$ range from 145 to 1000 GeV. We also interpret the results in the context of an electroweak singlet extension of the standard model.

5 data tables

Upper limits at 95\% CL on the cross section for a heavy Higgs boson decaying to a pair of W bosons as a function of its mass and its width relative to a SM-like Higgs boson.

Upper limits at 95\% CL on the cross section for a heavy Higgs boson decaying to a pair of Z bosons as a function of its mass and its width relative to a SM-like Higgs boson.

Upper limits at 95% CL on the cross section for a heavy Higgs boson as a function of its mass and its width relative to a SM-like Higgs boson. Both, gluon-gluon fusion and VBF production processes are combined, assuming a SM-like ratio between the two.

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Simultaneous measurements of the $t\bar{t}$, $W^+W^-$, and $Z/\gamma^{*}\rightarrow\tau\tau$ production cross-sections in $pp$ collisions at $\sqrt{s} = 7$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev. D91 (2015) 052005, 2015.
Inspire Record 1304455 DOI 10.17182/hepdata.67345

<p>Simultaneous measurements of the <inline-formula><mml:math display="inline"><mml:mi>t</mml:mi><mml:mover accent="true"><mml:mi>t</mml:mi><mml:mo accent="true" stretchy="false">¯</mml:mo></mml:mover></mml:math></inline-formula>, <inline-formula><mml:math display="inline"><mml:msup><mml:mi>W</mml:mi><mml:mo>+</mml:mo></mml:msup><mml:msup><mml:mi>W</mml:mi><mml:mo>-</mml:mo></mml:msup></mml:math></inline-formula>, and <inline-formula><mml:math display="inline"><mml:mi>Z</mml:mi><mml:mo stretchy="false">/</mml:mo><mml:msup><mml:mi>γ</mml:mi><mml:mo>*</mml:mo></mml:msup><mml:mo stretchy="false">→</mml:mo><mml:mi>τ</mml:mi><mml:mi>τ</mml:mi></mml:math></inline-formula> production cross-sections using an integrated luminosity of <inline-formula><mml:math display="inline"><mml:mrow><mml:mn>4.6</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:msup><mml:mrow><mml:mi>fb</mml:mi></mml:mrow><mml:mrow><mml:mo>-</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msup></mml:mrow></mml:math></inline-formula> of <inline-formula><mml:math display="inline"><mml:mi>p</mml:mi><mml:mi>p</mml:mi></mml:math></inline-formula> collisions at <inline-formula><mml:math display="inline"><mml:msqrt><mml:mi>s</mml:mi></mml:msqrt><mml:mo>=</mml:mo><mml:mn>7</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>TeV</mml:mi></mml:math></inline-formula> collected by the ATLAS detector at the LHC are presented. Events are selected with two high transverse momentum leptons consisting of an oppositely charged electron and muon pair. The three processes are separated using the distributions of the missing transverse momentum of events with zero and greater than zero jet multiplicities. Measurements of the fiducial cross-section are presented along with results that quantify for the first time the underlying correlations in the predicted and measured cross-sections due to proton parton distribution functions. These results indicate that the correlated next-to-leading-order predictions for <inline-formula><mml:math display="inline"><mml:mi>t</mml:mi><mml:mover accent="true"><mml:mi>t</mml:mi><mml:mo accent="true" stretchy="false">¯</mml:mo></mml:mover></mml:math></inline-formula> and <inline-formula><mml:math display="inline"><mml:mi>Z</mml:mi><mml:mo stretchy="false">/</mml:mo><mml:msup><mml:mi>γ</mml:mi><mml:mo>*</mml:mo></mml:msup><mml:mo stretchy="false">→</mml:mo><mml:mi>τ</mml:mi><mml:mi>τ</mml:mi></mml:math></inline-formula> underestimate the data, while those at next-to-next-to-leading-order generally describe the data well. The full cross-sections are measured to be <inline-formula><mml:math display="inline"><mml:mrow><mml:mi>σ</mml:mi><mml:mo stretchy="false">(</mml:mo><mml:mi>t</mml:mi><mml:mover accent="true"><mml:mrow><mml:mi>t</mml:mi></mml:mrow><mml:mrow><mml:mo accent="true" stretchy="false">¯</mml:mo></mml:mrow></mml:mover><mml:mo stretchy="false">)</mml:mo><mml:mo>=</mml:mo><mml:mn>181.2</mml:mn><mml:mo>±</mml:mo><mml:mn>2.</mml:mn><mml:msubsup><mml:mrow><mml:mn>8</mml:mn></mml:mrow><mml:mrow><mml:mo>-</mml:mo><mml:mn>9.5</mml:mn></mml:mrow><mml:mrow><mml:mo>+</mml:mo><mml:mn>9.7</mml:mn></mml:mrow></mml:msubsup><mml:mo>±</mml:mo><mml:mn>3.3</mml:mn><mml:mo>±</mml:mo><mml:mn>3.3</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>pb</mml:mi></mml:mrow></mml:math></inline-formula>, <inline-formula><mml:math display="inline"><mml:mrow><mml:mi>σ</mml:mi><mml:mo stretchy="false">(</mml:mo><mml:msup><mml:mrow><mml:mi>W</mml:mi></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msup><mml:msup><mml:mrow><mml:mi>W</mml:mi></mml:mrow><mml:mrow><mml:mo>-</mml:mo></mml:mrow></mml:msup><mml:mo stretchy="false">)</mml:mo><mml:mo>=</mml:mo><mml:mn>53.3</mml:mn><mml:mo>±</mml:mo><mml:mn>2.</mml:mn><mml:msubsup><mml:mrow><mml:mn>7</mml:mn></mml:mrow><mml:mrow><mml:mo>-</mml:mo><mml:mn>8.0</mml:mn></mml:mrow><mml:mrow><mml:mo>+</mml:mo><mml:mn>7.3</mml:mn></mml:mrow></mml:msubsup><mml:mo>±</mml:mo><mml:mn>1.0</mml:mn><mml:mo>±</mml:mo><mml:mn>0.5</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>pb</mml:mi></mml:mrow></mml:math></inline-formula>, and <inline-formula><mml:math display="inline"><mml:mrow><mml:mi>σ</mml:mi><mml:mo stretchy="false">(</mml:mo><mml:mi>Z</mml:mi><mml:mo stretchy="false">/</mml:mo><mml:msup><mml:mrow><mml:mi>γ</mml:mi></mml:mrow><mml:mrow><mml:mo>*</mml:mo></mml:mrow></mml:msup><mml:mo stretchy="false">→</mml:mo><mml:mi>τ</mml:mi><mml:mi>τ</mml:mi><mml:mo stretchy="false">)</mml:mo><mml:mo>=</mml:mo><mml:mn>1174</mml:mn><mml:mo>±</mml:mo><mml:mn>2</mml:mn><mml:msubsup><mml:mrow><mml:mn>4</mml:mn></mml:mrow><mml:mrow><mml:mo>-</mml:mo><mml:mn>87</mml:mn></mml:mrow><mml:mrow><mml:mo>+</mml:mo><mml:mn>72</mml:mn></mml:mrow></mml:msubsup><mml:mo>±</mml:mo><mml:mn>21</mml:mn><mml:mo>±</mml:mo><mml:mn>9</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>pb</mml:mi></mml:mrow></mml:math></inline-formula>, where the cited uncertainties are due to statistics, systematic effects, luminosity and the LHC beam energy measurement, respectively. The <inline-formula><mml:math display="inline"><mml:msup><mml:mi>W</mml:mi><mml:mo>+</mml:mo></mml:msup><mml:msup><mml:mi>W</mml:mi><mml:mo>-</mml:mo></mml:msup></mml:math></inline-formula> measurement includes the small contribution from Higgs boson decays, <inline-formula><mml:math display="inline"><mml:mi>H</mml:mi><mml:mo stretchy="false">→</mml:mo><mml:msup><mml:mi>W</mml:mi><mml:mo>+</mml:mo></mml:msup><mml:msup><mml:mi>W</mml:mi><mml:mo>-</mml:mo></mml:msup></mml:math></inline-formula>.</p>

1 data table

Total $t\bar{t}$, $WW$, and $Z/\gamma^* \rightarrow \tau\tau$ cross-sections as measured simultaneously in this analysis with symmetrized uncertainties.


Search for new phenomena in the $W W$ to $\ell \nu \ell$' $\nu$' final state in $pp$ collisions at $\sqrt{s}=7$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
Phys.Lett. B718 (2013) 860-878, 2013.
Inspire Record 1127504 DOI 10.17182/hepdata.59354
5 data tables

Expected and observed 95% upper limits on cross section time branching ration for pp --> Graviton* < W+ W- >.

Expected and observed 95% upper limits on cross section time branching ration for pp --> Graviton*(bulk) < W+ W- >.

Observed and predicted W+W- transverse mass distribution in the MU-MU channel. Also tabulated are the predictions for a RS graviton of mass 1000 GeV and a bulk RS graviton with mass 600 GeV.

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Measurement of $W^+ W^-$ production and search for the Higgs boson in pp collisions at $\sqrt s=7$ TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Phys.Lett. B699 (2011) 25-47, 2011.
Inspire Record 890910 DOI 10.17182/hepdata.57953

A measurement of WW production in pp collisions at sqrt(s) = 7 TeV and a search for the Higgs boson are reported. The WW candidates are selected in events with two leptons, either electrons or muons. The measurement is performed using LHC data recorded with the CMS detector, corresponding to an integrated luminosity of 36 inverse picobarns. The pp to WW cross section is measured to be 41.1 +/- 15.3 (stat) +/- 5.8 (syst) +/- 4.5 (lumi) pb, consistent with the standard model prediction. Limits on WW gamma and WWZ anomalous triple gauge couplings are set. The search for the standard model Higgs boson in the WW decay mode does not reveal any evidence of excess above backgrounds. Limits are set on the production of the Higgs boson in the context of the standard model and in the presence of a sequential fourth family of fermions with high masses. In the latter context, a Higgs boson with mass between 144 and 207 GeV is ruled out at 95% confidence level.

1 data table

The measured W+ W- cross section.


Measurement of the $W^+ W^-$ Production Cross Section and Search for Anomalous $WW \gamma$ and $WWZ$ Couplings in $p \bar{p}$ Collisions at $\sqrt{s}=1.96$~TeV

The CDF collaboration Aaltonen, T. ; Adelman, J. ; Alvarez Gonzalez, B. ; et al.
Phys.Rev.Lett. 104 (2010) 201801, 2010.
Inspire Record 841021 DOI 10.17182/hepdata.54291

This Letter describes the current most precise measurement of the $W$ boson pair production cross section and most sensitive test of anomalous $WW\gamma$ and $WWZ$ couplings in $p \bar p$ collisions at a center-of-mass energy of 1.96 TeV. The $WW$ candidates are reconstructed from decays containing two charged leptons and two neutrinos, where the charged leptons are either electrons or muons. Using data collected by the CDF II detector from 3.6 fb$^{-1}$ of integrated luminosity, a total of 654 candidate events are observed with an expected background contribution of $320 \pm 47$ events. The measured total cross section is $\sigma (p \bar p \to W^+ W^- + X) = 12.1 \pm 0.9 \textrm{(stat)} ^{+1.6}_{-1.4} \textrm{(syst)}$ pb, which is in good agreement with the standard model prediction. The same data sample is used to place constraints on anomalous $WW\gamma$ and $WWZ$ couplings.

1 data table

Measured cross section for inclusive W+ W- production.


Measurement of the WW+WZ Production Cross Section Using the Lepton+Jets Final State at CDF II

The CDF collaboration Aaltonen, T. ; Adelman, J. ; Alvarez Gonzalez, B. ; et al.
Phys.Rev.Lett. 104 (2010) 101801, 2010.
Inspire Record 837610 DOI 10.17182/hepdata.54292

We report two complementary measurements of the WW+WZ cross section in the final state consisting of an electron or muon, missing transverse energy, and jets, performed using p\bar{p} collision data at sqrt{s} = 1.96 TeV collected by the CDF II detector. The first method uses the dijet invariant mass distribution while the second more sensitive method uses matrix-element calculations. The result from the second method has a signal significance of 5.4 sigma and is the first observation of WW+WZ production using this signature. Combining the results gives sigma_{WW+WZ} = 16.0 +/- 3.3 pb, in agreement with the standard model prediction.

3 data tables

Cross section from the combined analysis.. Error is combined statistics and systematics.

Cross section from method one.

Cross section from method two.


Model-independent measurement of the $W$ boson helicity in top quark decays at D0

The D0 collaboration Abazov, V.M. ; Abbott, B. ; Abolins, M. ; et al.
Phys.Rev.Lett. 100 (2008) 062004, 2008.
Inspire Record 767094 DOI 10.17182/hepdata.47072

We present the first model-independent measurement of the helicity of $W$ bosons produced in top quark decays, based on a 1 fb$^{-1}$ sample of candidate $t\bar{t}$ events in the dilepton and lepton plus jets channels collected by the D0 detector at the Fermilab Tevatron $p\bar{p}$ Collider. We reconstruct the angle $\theta^*$ between the momenta of the down-type fermion and the top quark in the $W$ boson rest frame for each top quark decay. A fit of the resulting \costheta distribution finds that the fraction of longitudinal $W$ bosons $f_0 = 0.425 \pm 0.166 \hbox{(stat.)} \pm 0.102 \hbox{(syst.)}$ and the fraction of right-handed $W$ bosons $f_+ = 0.119 \pm 0.090 \hbox{(stat.)} \pm 0.053 \hbox{(syst.)}$, which is consistent at the 30% C.L. with the standard model.

6 data tables

COS(THETA*) distribution for leptonic W decay in lepton+jets events.. Data are read from plots and errors are statistcial (sqrt(N)).

COS(THETA*) distribution for hadronic W decay in lepton+jets events.. Data are read from plots and errors are statistcial (sqrt(N)).

COS(THETA*) distribution for W decay in dilepton events.. Data are read from plots and errors are statistcial (sqrt(N)).

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W boson polarization at LEP2

The OPAL collaboration
Phys.Lett. B585 (2004) 223-236, 2004.
Inspire Record 635790 DOI 10.17182/hepdata.49660

Elements of the spin density matrix for W bosons in e+e- -> W+W- -> qqln events are measured from data recorded by the OPAL detector at LEP. This information is used calculate polarised differential cross-sections and to search for CP-violating effects. Results are presented for W bosons produced in e+e- collisions with centre-of-mass energies between 183 GeV and 209 GeV. The average fraction of W bosons that are longitudinally polarised is found to be (23.9 +- 2.1 +- 1.1)% compared to a Standard Model prediction of (23.9 +- 0.1)%. All results are consistent with CP conservation.

7 data tables

The fraction of longitudinal polarization for leptonically and hadronically decaying W bosons. The average values for all the centre of mass energies and for both lepton and hadron decay combined are also given.

The luminosity weighted average over all the centre of mass energies of the diagonal elements of the RHO++ and RHO-- SDM as a function of the cosine of the angle of the W- boson for the leptonic decay channel.

The luminosity weighted average over all the centre of mass energies of the diagonal element of the RHO00 SDM as a function of the cosine of the angle of the W- boson for both leptonic and hadronic decay channels, and combined.

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Measurement of the $W^{+} W^{-} \gamma$ cross-section and direct limits on anomalous quartic gauge boson couplings at LEP

The L3 collaboration Acciarri, M. ; Achard, P. ; Adriani, O. ; et al.
Phys.Lett. B490 (2000) 187-195, 2000.
Inspire Record 531570 DOI 10.17182/hepdata.49908

The process e+e- -> W+W-gamma is analysed using the data collected with the L3 detector at LEP at a centre-of-mass energy of 188.6GeV, corresponding to an integrated luminosity of 176.8pb^-1. Based on a sample of 42 selected W+W- candidates containing an isolated hard photon, the W+W-gamma cross section, defined within phase-space cuts, is measured to be: sigma_WWgamma = 290 +/- 80 +/- 16 fb, consistent with the Standard Model expectation. Including the process e+e- -> nu nu gamma gamma, limits are derived on anomalous contributions to the Standard Model quartic vertices W+W- gamma gamma and W+W-Z gamma at 95% CL: -0.043 GeV^-2 &lt; a_0/Lambda^2 &lt; 0.043 GeV^-2 0.08 GeV^-2 &lt; a_c/Lambda^2 &lt; 0.13 GeV^-2 0.41 GeV^-2 &lt; a_n/Lambda^2 &lt; 0.37 GeV^-2.

2 data tables

Measured cross section within the limits of the cuts. THETA(C=GAMMA) is the angle between the photon and the beam axis. ALPHA(C=GAMMA) is the angle between the photon and that of the closest charged lepton or jet.

95 PCT confidence limits on the anomolous contributions.


Measurement of the $W^{+} W^{-} \gamma$ cross-section and first direct limits on anomalous electroweak quartic gauge couplings

The OPAL collaboration Abbiendi, G. ; Ackerstaff, K. ; Akesson, P.F. ; et al.
Phys.Lett. B471 (1999) 293-307, 1999.
Inspire Record 509394 DOI 10.17182/hepdata.49088

A study of W+W- events accompanied by hard photon radiation produced in e+e- collisions at LEP is presented. Events consistent with two on-shell W-bosons and an isolated photon are selected from 183pb^-1 of data recorded at root{s}=189GeV. From these data, 17 W+W-gamma candidates are selected with photon energy greater than 10GeV, consistent with the Standard Model expectation. These events are used to measure the e+e- to W+W-gamma cross-section within a set of geometric and kinematic cuts; sigma{W+W-gamma} = 136+-37+-8 fb, where the first error is statistical and the second systematic. The photon energy spectrum is used to set the first direct, albeit weak, limits on possible anomalous contributions to the {W+ W- gamma gamma} and {W+ W- gamma Z0} vertices: -0.070GeV^{-2} < a_0/Lambda^2 < 0.070GeV^{-2}, -0.13GeV^{-2} < a_c/Lambda^2 < 0.19GeV^{-2}, -0.61GeV^{-2} < a_n/Lambda^2 < 0.57GeV^{-2}, where Lambda represents the energy scale for new physics.

2 data tables

Measured cross section within the kinematic and geometric cuts. THETA(C=GAMMA) is the angle between the photon and the closest jet, and THETA(C=LEPTON) is the angle between the photon and the lepton.

95 PCT confidence limits on possible anomalous contributions.


Observation of $W^+ W^-$ production in $\bar{p}p$ collisions at $\sqrt{s} = 1.8$ TeV

The CDF collaboration Abe, F. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.Lett. 78 (1997) 4536-4540, 1997.
Inspire Record 423258 DOI 10.17182/hepdata.42247
1 data table

No description provided.


Search for $W$ boson pair production in $p \bar{p}$ collisions at $\sqrt{s}$ = 1.8-TeV

The D0 collaboration Abachi, S. ; Abbott, B. ; Abolins, M. ; et al.
Conference Paper, 1995.
Inspire Record 398747 DOI 10.17182/hepdata.43019
1 data table

Upper limit at the 95% C.L.