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Measurement of $WZ$ production in proton-proton collisions at $\sqrt{s}=7$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
Eur.Phys.J. C72 (2012) 2173, 2012.
Inspire Record 1126131 DOI 10.17182/hepdata.59721

A study of WZ production in proton-proton collisions at sqrt(s) = 7 TeV is presented using data corresponding to an integrated luminosity of 4.6 fb^-1 collected with the ATLAS detector at the Large Hadron Collider in 2011. In total, 317 candidates, with a background expectation of 68+/-10 events, are observed in double-leptonic decay final states with electrons, muons and missing transverse momentum. The total cross-section is determined to be sigma_WZ(tot) = 19.0+1.4/-1.3(stat.)+/-0.9(syst.)+/-0.4(lumi.) pb, consistent with the Standard Model expectation of 17.6+1.1/-1.0 pb. Limits on anomalous triple gauge boson couplings are derived using the transverse momentum spectrum of Z bosons in the selected events. The cross section is also presented as a function of Z boson transverse momentum and diboson invariant mass.

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Measurement of the $W \to \ell\nu$ and $Z/\gamma^* \to \ell\ell$ production cross sections in proton-proton collisions at $\sqrt{s} = 7$ TeV with the ATLAS detector

The ATLAS collaboration Aad, G. ; Abbott, B. ; Abdallah, J. ; et al.
JHEP 1012 (2010) 060, 2010.
Inspire Record 872570 DOI 10.17182/hepdata.56744

First measurements of the W -> lnu and Z/gamma* -> ll (l = e, mu) production cross sections in proton-proton collisions at sqrt(s) = 7 TeV are presented using data recorded by the ATLAS experiment at the LHC. The results are based on 2250 W -> lnu and 179 Z/gamma* -> ll candidate events selected from a data set corresponding to an integrated luminosity of approximately 320 nb-1. The measured total W and Z/gamma*-boson production cross sections times the respective leptonic branching ratios for the combined electron and muon channels are $\stotW$ * BR(W -> lnu) = 9.96 +- 0.23(stat) +- 0.50(syst) +- 1.10(lumi) nb and $\stotZg$ * BR(Z/gamma* -> ll) = 0.82 +- 0.06(stat) +- 0.05(syst) +- 0.09(lumi) nb (within the invariant mass window 66 < m_ll < 116 GeV). The W/Z cross-section ratio is measured to be 11.7 +- 0.9(stat) +- 0.4(syst). In addition, measurements of the W+ and W- production cross sections and of the lepton charge asymmetry are reported. Theoretical predictions based on NNLO QCD calculations are found to agree with the measurements.

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Measurement of $Z$ boson Production in Pb+Pb Collisions at $\sqrt{s_{NN}}=2.76$ TeV with the ATLAS Detector

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
Phys.Rev.Lett. 110 (2013) 022301, 2013.
Inspire Record 1193044 DOI 10.17182/hepdata.60336
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Extraction of the width of the $W$ boson from measurements of $\sigma(p\bar{p} \to W + X) \times B(W \to e \nu)$ and $\sigma(p\bar{p} \to Z + X) \times B(Z \to e e)$ and their ratio

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Rev. D61 (2000) 072001, 2000.
Inspire Record 501703 DOI 10.17182/hepdata.42085

We report on measurements of inclusive cross sections times branching fractions into electrons for W and Z bosons produced in ppbar collisions at sqrts=1.8 TeV.From an integrated luminosity of 84.5 inverse pb recorded in 1994--1995 using the D0 detector at the Fermilab Tevatron, we determine sigma(ppbar->W+X)B(W->e nu) = 2310 +- 10(stat) +- 50(syst) +- 100(lum) pb and sigma(ppbar->Z+X)B(Z->e e) = 221 +- 3(stat) +- 4(syst) +- 10(lum) pb. From these, we derive their Ratio R = 10.43 +- 0.15(stat) +- 0.20(syst) +- 0.10(NLO), B(W->e nu) = 0.1066 +- 0.0015(stat) +- 0.0021(syst) +- 0.0011(theory)+- 0.0011(NLO), and Gamma_W = 2.130 +- 0.030(stat) +- 0.041(syst) +- 0.022(theory) +- 0.021(NLO) GeV. We use the latter to set a 95% confidence level upper limit on the partial decay width of the W boson into non-standard model final states, Gamma_W^{inv}, of 0.168 GeV. Combining these results with those from the 1992--1993 data gives R = 10.54 +- 0.24, Gamma_W = 2.107 +- 0.054 GeV, and a 95% C.L. upper limit on Gamma_W^{inv} of 0.132 GeV. Using a sample with a luminosity of 505 inverse nb taken at sqrts=630 GeV, we measure sigma(ppbar->W+X)B(W->e nu) = 658 +- 67 pb.

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Measurement of the $p \bar{p} \to WZ + X$ cross-section at $\sqrt{s}$ = 1.96-TeV and limits on WWZ trilinear gauge couplings

The D0 collaboration Abazov, V.M. ; Abbott, B. ; Abolins, Maris A. ; et al.
Phys.Rev. D76 (2007) 111104, 2007.
Inspire Record 761244 DOI 10.17182/hepdata.42722

We present measurements of the process $p\bar{p} \to WZ+X \to \ell^{\prime} \nu_{\ell^{\prime}} \ell \bar{\ell}$ at $\sqrt{s}=1.96$ TeV, where $\ell$ and $\ell^{\prime}$ are electrons or muons. Using 1 fb$^{-1}$ of data from the D0 experiment, we observe 13 candidates with an expected background of $4.5\pm0.6$ events and measure a cross section $\sigma(WZ)=2.7^{+1.7}_{-1.3}$ pb. From the number of observed events and the $Z$ boson transverse momentum distribution, we limit the trilinear $WWZ$ gauge couplings to $-0.17 \le \lambda_Z \le 0.21$ $(\Delta \kappa_Z = 0)$ at the 95% C.L. for a form factor scale $\Lambda=2$ TeV. Further, assuming that $\Delta g^Z_1 = \Delta\kappa_Z$, we find $-0.12 \le \Delta\kappa_Z \le 0.29$ $(\lambda_Z=0)$ at the 95% C.L. These are the most restrictive limits on the $WWZ$ couplings available to date.

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Observation of Z decays to four leptons with the CMS detector at the LHC

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
JHEP 1212 (2012) 034, 2012.
Inspire Record 1190671 DOI 10.17182/hepdata.65757

The first observation of the Z boson decaying to four leptons in proton-proton collisions is presented. The analyzed data set corresponds to an integrated luminosity of 5.02 inverse femtobarns at sqrt(s) = 7 TeV collected by the CMS detector at the Large Hadron Collider. A pronounced resonance peak, with a statistical significance of 9.7 sigma, is observed in the distribution of the invariant mass of four leptons (electrons and/or muons) with mass and width consistent with expectations for Z boson decays. The branching fraction and cross section reported here are defined by phase space restrictions on the leptons, namely, 80 < m[4l] < 100 GeV, where m[4l] is the invariant mass of the four leptons, and m[ll] > 4 GeV for all pairs of leptons, where m[ll] is the two-lepton invariant mass. The measured branching fraction is B(Z to 4l) = (4.2 /+0.9/-0.8 (stat.) +/- 0.2 (syst.)) 10E-6 and agrees with the standard model prediction of 4.45 10E-6. The measured cross section times branching fraction is sigma(pp to Z) B(Z to 4 l) = 112 +23/-20 (stat.) +7/-5 (syst.) +3/-2 (lumi.) fb, also consistent with the standard model prediction of 120 fb. The four-lepton mass peak arising from Z to 4 l decays provides a calibration channel for the Higgs boson search in the H to ZZ to 4 l decay mode.

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Measurement of W+W- and ZZ production cross sections in pp collisions at sqrt(s) = 8 TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Phys.Lett. B721 (2013) 190-211, 2013.
Inspire Record 1215317 DOI 10.17182/hepdata.62680

The W^+W^- and ZZ production cross sections are measured in proton-proton collisions at s=8 TeV with the CMS experiment at the LHC in data samples corresponding to an integrated luminosity of up to 5.3 fb^-^1. The measurements are performed in the leptonic decay modes W^+W^-->@?^'@n@?^''@n and ZZ->2@?2@?^', where @?=e,@m and @?^'(@?^'')=e,@m,@t. The measured cross sections @s(pp->W^+W^-)=69.9+/-2.8(stat.)+/-5.6(syst.)+/-3.1(lum.) pb and @s(pp->ZZ)=8.4+/-1.0(stat.)+/-0.7(syst.)+/-0.4(lum.) pb, for both Z bosons produced in the mass region 60<m_Z<120 GeV, are consistent with standard model predictions. These are the first measurements of the diboson production cross sections at s=8 TeV.

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Properties of jets in Z boson events from 1.8 TeV $\bar{p}p$ collisions

The CDF collaboration Abe, F. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.Lett. 77 (1996) 448-453, 1996.
Inspire Record 416570 DOI 10.17182/hepdata.42318

We present a study of events with Z bosons and hadronic jets produced in $\overline{p}p$ collisions at a center-of-mass energy of 1.8 TeV. The data consist of 6708 $Z \rightarrow e~+e~-$ decays from 106 pb$~{-1}$ of integrated luminosity collected using the CDF detector at the Tevatron Collider. The Z $+ \ge n$ jet cross sections and jet production properties have been measured for n = 1 to 4. The data compare well to predictions of leading order QCD matrix element calculations with added gluon radiation and simulated parton fragmentation.

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First Measurement of $Z Z$ Production in panti-p Collisions at $\sqrt{s}$ = 1.96-TeV

The CDF collaboration Aaltonen, T. ; Adelman, Jahred A. ; Akimoto, T. ; et al.
Phys.Rev.Lett. 100 (2008) 201801, 2008.
Inspire Record 778518 DOI 10.17182/hepdata.42695

We report the first measurement of the cross section for Z boson pair production at a hadron collider. This result is based on a data sample corresponding to 1.9 fb-1 of integrated luminosity from ppbar collisions at sqrt{s} = 1.96 TeV collected with the CDF II detector at the Fermilab Tevatron. In the llll channel, we observe three ZZ candidates with an expected background of 0.096^{+0.092}_{-0.063} events. In the llnunu channel, we use a leading-order calculation of the relative ZZ and WW event probabilities to discriminate between signal and background. In the combination of llll and llnunu channels, we observe an excess of events with a probability of $5.1\times 10^{-6}$ to be due to the expected background. This corresponds to a significance of 4.4 standard deviations. The measured cross section is sigma(ppbar -> ZZ) = 1.4^{+0.7}_{-0.6} (stat.+syst.) pb, consistent with the standard model expectation.

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Properties of jets in $W$ boson events from 1.8 TeV $\bar{p}p$ collisions

The CDF collaboration Abe, F. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.Lett. 79 (1997) 4760-4765, 1997.
Inspire Record 448076 DOI 10.17182/hepdata.54006

We present a study of events with W bosons and hadronic jets produced in pbar p collisions at a center of mass energy of 1.8 TeV. The data consist of 51400 W^+/- -> e^+/- nu decay candidates from 108 pb^-1 of integrated luminosity collected with the CDF detector at the Tevatron Collider. The cross sections and jet production properties have been measured for W + \geq 1 to \geq 4 jet events. The data are compared to predictions of leading order QCD matrix element calculations with added gluon radiation and simulated fragmentation.

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Search for anomalous production of events with three or more leptons in $pp$ collisions at $\sqrt(s) =$ 8 TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Phys.Rev. D90 (2014) 032006, 2014.
Inspire Record 1291940 DOI 10.17182/hepdata.64435
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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.

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Measurement of the production cross sections for a Z boson and one or more b jets in pp collisions at sqrt(s) = 7 TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
JHEP 1406 (2014) 120, 2014.
Inspire Record 1280529 DOI 10.17182/hepdata.64748

The production of a Z boson, decaying into two leptons and produced in association with one or more b jets, is studied using proton-proton collisions delivered by the LHC at a centre-of-mass energy of 7 TeV. The data were recorded in 2011 with the CMS detector and correspond to an integrated luminosity of 5 fb(−1). The Z(ℓℓ) + b-jets cross sections (where ℓℓ = μμ or ee) are measured separately for a Z boson produced with exactly one b jet and with at least two b jets. In addition, a cross section ratio is extracted for a Z boson produced with at least one b jet, relative to a Z boson produced with at least one jet. The measured cross sections are compared to various theoretical predictions, and the data favour the predictions in the five-flavour scheme, where b quarks are assumed massless. The kinematic properties of the reconstructed particles are compared with the predictions from the MadGraph event generator using the pythia parton shower simulation.

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Measurements of the $\mathrm{Z}$ $\mathrm{Z}$ production cross sections in the $2\mathrm{l} 2\nu $ channel in proton–proton collisions at $\sqrt{s} = 7$ and $8~\mathrm{TeV} $ and combined constraints on triple gauge couplings

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Eur.Phys.J. C75 (2015) 511, 2015.
Inspire Record 1353393 DOI 10.17182/hepdata.69984

Measurements of the $\mathrm{Z}$ $\mathrm{Z}$ production cross sections in proton–proton collisions at center-of-mass energies of 7 and 8 $~\mathrm{TeV}$ are presented. Candidate events for the leptonic decay mode $\mathrm{Z}\mathrm{Z}\rightarrow 2\mathrm{l} 2\nu $ , where $\mathrm{l}$ denotes an electron or a muon, are reconstructed and selected from data corresponding to an integrated luminosity of 5.1 (19.6) $\,\text {fb}^\text {-1}$ at 7 (8) $~\mathrm{TeV}$ collected with the CMS experiment. The measured cross sections, $\sigma (\mathrm {p}\mathrm {p}\rightarrow \mathrm{Z}\mathrm{Z}) = 5.1_{-1.4}^{+1.5}\,\text {(stat)} \,_{-1.1}^{+1.4}\,\text {(syst)} \pm 0.1\,\text {(lumi)} \text {~pb} $ at 7 $~\mathrm{TeV}$ , and $7.2_{-0.8}^{+0.8}\,\text {(stat)} \,_{-1.5}^{+1.9}\,\text {(syst)} \,\pm \, 0.2\,\text {(lumi)} \text {~pb} $ at 8 $~\mathrm{TeV}$ , are in good agreement with the standard model predictions with next-to-leading-order accuracy. The selected data are analyzed to search for anomalous triple gauge couplings involving the $\mathrm{Z}$ $\mathrm{Z}$ final state. In the absence of any deviation from the standard model predictions, limits are set on the relevant parameters. These limits are then combined with the previously published CMS results for $\mathrm{Z}$ $\mathrm{Z}$ in 4 $\mathrm{l}$ final states, yielding the most stringent constraints on the anomalous couplings.

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Measurement of the Zγ Production Cross Section in pp Collisions at 8 TeV and Search for Anomalous Triple Gauge Boson Couplings

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
JHEP 1504 (2015) 164, 2015.
Inspire Record 1345354 DOI 10.17182/hepdata.66985

The cross section for the production of Zγ in proton-proton collisions at 8 TeV is measured based on data collected by the CMS experiment at the LHC corresponding to an integrated luminosity of 19.5 fb$^{−1}$. Events with an oppositely-charged pair of muons or electrons together with an isolated photon are selected. The differential cross section as a function of the photon transverse momentum is measured inclusively and exclusively, where the exclusive selection applies a veto on central jets. The observed cross sections are compatible with the expectations of next-to-next-to-leading-order quantum chromodynamics. Limits on anomalous triple gauge couplings of ZZγ and Zγγ are set that improve on previous experimental results obtained with the charged lepton decay modes of the Z boson.

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Angular coefficients of Z bosons produced in pp collisions at $\sqrt{s}$ = 8 TeV and decaying to $\mu^+ \mu^-$ as a function of transverse momentum and rapidity

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Lett. B750 (2015) 154-175, 2015.
Inspire Record 1359451 DOI 10.17182/hepdata.69285

Measurements of the five most significant angular coefficients, A[0] through A[4], for Z bosons produced in pp collisions at $\sqrt{s}$ = 8 TeV and decaying to $\mu^+ \mu^-$ are presented as a function of the transverse momentum and rapidity of Z boson. The integrated luminosity of the dataset collected with the CMS detector at the LHC corresponds to 19.7 inverse femtobarns. These measurements provide comprehensive information about Z boson production mechanisms, and are compared to QCD predictions at leading order, next-to-leading order, and next-to-next-to-leading order in perturbation theory.

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Measurements of differential and double-differential Drell-Yan cross sections in proton-proton collisions at 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Eur.Phys.J. C75 (2015) 147, 2015.
Inspire Record 1332509 DOI 10.17182/hepdata.69869

Measurements of the differential and double-differential Drell–Yan cross sections in the dielectron and dimuon channels are presented. They are based on proton–proton collision data at $\sqrt{s} = 8\,\text {TeV} $ recorded with the CMS detector at the LHC and corresponding to an integrated luminosity of 19.7 $\,\text {fb}^{-1}$ . The measured inclusive cross section in the $\mathrm{Z}$ peak region (60–120 $\,\text {GeV}$ ), obtained from the combination of the dielectron and dimuon channels, is $1138 \pm 8\,\text {(exp)} \pm 25\,\text {(theo)} \pm 30\,\text {(lumi)} \text {\,pb} $ , where the statistical uncertainty is negligible. The differential cross section $\mathrm{d}\sigma /\mathrm{d}{}m$ in the dilepton mass range 15–2000 $\,\text {GeV}$ is measured and corrected to the full phase space. The double-differential cross section $\mathrm{d}^2\sigma /\mathrm{d}{}m\,\mathrm{d}|y |$ is also measured over the mass range 20 to 1500 $\,\text {GeV}$ and absolute dilepton rapidity from 0 to 2.4. In addition, the ratios of the normalized differential cross sections measured at $\sqrt{s} = 7$ and 8 $\,\text {TeV}$ are presented. These measurements are compared to the predictions of perturbative QCD at next-to-leading and next-to-next-to-leading (NNLO) orders using various sets of parton distribution functions (PDFs). The results agree with the NNLO theoretical predictions computed with fewz 3.1 using the CT10 NNLO and NNPDF2.1 NNLO PDFs. The measured double-differential cross section and ratio of normalized differential cross sections are sufficiently precise to constrain the proton PDFs.

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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.

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Search for a pseudoscalar boson decaying into a Z boson and the 125 GeV Higgs boson in $ℓ^+ℓ^−b\overline{b}$ final states

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Lett. B748 (2015) 221-243, 2015.
Inspire Record 1362177 DOI 10.17182/hepdata.70527

Results are reported on a search for decays of a pseudoscalar A boson into a Z boson and a light scalar h boson, where the Z boson decays into a pair of oppositely-charged electrons or muons, and the h boson decays into bb¯ . The search is based on data from proton–proton collisions at a center-of-mass energy s=8 TeV collected with the CMS detector, corresponding to an integrated luminosity of 19.7 fb−1 . The h boson is assumed to be the standard model-like Higgs boson with a mass of 125 GeV. With no evidence for signal, upper limits are obtained on the product of the production cross section and the branching fraction of the A boson in the Zh channel. Results are also interpreted in the context of two Higgs doublet models.

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Measurement of the $ \mathrm{ Z } \gamma \rightarrow \nu \bar{\nu} \gamma$ production cross section in pp collisions at $\sqrt{s}=$ 8 TeV and limits on anomalous $ \mathrm{ ZZ } \gamma$ and $ \mathrm{Z} \gamma \gamma$ trilinear gauge boson couplings

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Lett. B760 (2016) 448-468, 2016.
Inspire Record 1423069 DOI 10.17182/hepdata.74458

An inclusive measurement of the Zγ→νν‾γ production cross section in pp collisions at s=8TeV is presented, using data corresponding to an integrated luminosity of 19.6 fb −1 collected with the CMS detector at the LHC. This measurement is based on the observation of events with large missing energy and with a single photon with transverse momentum above 145 GeV and absolute pseudorapidity in the range |η|<1.44 . The measured Zγ→νν‾γ production cross section, 52.7±2.1 (stat)±6.4 (syst)±1.4 (lumi) fb , agrees well with the standard model prediction of 50.0−2.2+2.4 fb . A study of the photon transverse momentum spectrum yields the most stringent limits to date on the anomalous ZZγ and Zγγ trilinear gauge boson couplings.

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First measurement of $\sigma$ ($p \bar{p} \to Z^{)}$ . Br ($Z \to \tau \tau^{)}$ at $\sqrt{s}$ = 1.96- TeV

The D0 collaboration Abazov, V.M. ; Abbott, B. ; Abolins, M. ; et al.
Phys.Rev. D71 (2005) 072004, 2005.
Inspire Record 666357 DOI 10.17182/hepdata.50921

We present a measurement of the cross section for $Z$ production times the branching fraction to $\tau$ leptons, $\sigma \cdot$Br$(Z\to \tau^+ \tau^-)$, in $p \bar p$ collisions at $\sqrt{s}=$1.96 TeV in the channel in which one $\tau$ decays into $\mu \nu_{\mu} \nu_{\tau}$, and the other into $\rm {hadrons} + \nu_{\tau}$ or $e \nu_e \nu_{\tau}$. The data sample corresponds to an integrated luminosity of 226 pb$^{-1}$ collected with the D{\O}detector at the Fermilab Tevatron collider. The final sample contains 2008 candidate events with an estimated background of 55%. From this we obtain $\sigma \cdot$Br$(Z \to \tau^+ \tau^-)=237 \pm 15$(stat)$\pm 18$(sys)$ \pm 15$(lum) pb, in agreement with the standard model prediction.

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Measurement of the Inclusive $W$ and $Z$ Production Cross Sections in $pp$ Collisions at $\sqrt{s}=7$ TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
JHEP 1110 (2011) 132, 2011.
Inspire Record 919737 DOI 10.17182/hepdata.57964

A measurement of inclusive W and Z production cross sections in pp collisions at sqrt(s)=7 TeV is presented. The electron and muon decay channels are analyzed in a data sample collected with the CMS detector at the LHC and corresponding to an integrated luminosity of 36 inverse picobarns. The measured inclusive cross sections are sigma(pp-> WX) B(W-> l nu) = 10.30 +/- 0.02 (stat.) +/- 0.10 (syst.) +/- 0.10 (th.) +/- 0.41 (lumi.) nb and sigma(pp -> ZX) B(Z-> l^+l^-) = 0.974 +/- 0.007 (stat.) +/- 0.007 (syst.) +/- 0.018 (th.) +/- 0.039 (lumi.) nb, limited to the dilepton invariant mass range 60 to 120 GeV. The luminosity-independent cross section ratios are [sigma(pp->WX) B(W-> l nu)]/[sigma(pp-> ZX) B(Z->l^+l^-)] = 10.54 +/- 0.07 (stat.) +/- 0.08 (syst.) +/- 0.16 (th.) and [sigma(pp->W^+X) B(W^+ -> l^+nu)] / [sigma(pp->W^- X) B(W^- -> l^- nu)] = 1.421 +/- 0.006 (stat.) +/- 0.014 (syst.) +/- 0.029 (th.). The measured values agree with next-to-next-to-leading order QCD cross section calculations based on recent parton distribution functions.

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Study of Z boson production in PbPb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Phys.Rev.Lett. 106 (2011) 212301, 2011.
Inspire Record 890909 DOI 10.17182/hepdata.57943

A search for Z bosons in the mu^+mu^- decay channel has been performed in PbPb collisions at a nucleon-nucleon centre of mass energy = 2.76 TeV with the CMS detector at the LHC, in a 7.2 inverse microbarn data sample. The number of opposite-sign muon pairs observed in the 60--120 GeV/c2 invariant mass range is 39, corresponding to a yield per unit of rapidity (y) and per minimum bias event of (33.8 ± 5.5 (stat) ± 4.4 (syst)) 10^{-8}, in the |y|<2.0 range. Rapidity, transverse momentum, and centrality dependencies are also measured. The results agree with next-to-leading order QCD calculations, scaled by the number of incoherent nucleon-nucleon collisions.

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Measurement of the ratio $\sigma B (W \to e \nu) / \sigma B (Z^0 \to e^+ e^-)$ in $\bar{p}p$ collisions at $\sqrt{s} = 1.8$ TeV

The CDF collaboration Abe, F. ; Albrow, M. ; Amidei, D. ; et al.
Phys.Rev.Lett. 73 (1994) 220-224, 1994.
Inspire Record 373743 DOI 10.17182/hepdata.50100
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Measurement of $W \gamma$ and $Z \gamma$ production in $p\bar{p}$ collisions at $\sqrt{s} = 1.96$ TeV

The CDF collaboration Acosta, D. ; Adelman, J. ; Affolder, T. ; et al.
Phys.Rev.Lett. 94 (2005) 041803, 2005.
Inspire Record 660969 DOI 10.17182/hepdata.52428

The Standard Model predictions for $W\gamma$ and $Z\gamma$ production are tested using an integrated luminosity of 200 pb$^{-1}$ of \ppbar collision data collected at the Collider Detector at Fermilab. The cross sections are measured selecting leptonic decays of the $W$ and $Z$ bosons, and photons with transverse energy $E_T>7$ GeV that are well separated from leptons. The production cross sections and kinematic distributions for the $W\gamma$ and $Z\gamma$ are compared to SM predictions.

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