Four-lepton production in proton-proton collisions, pp→(Z/γ∗)(Z/γ∗)→4ℓ , where ℓ=e or μ , is studied at a center-of-mass energy of 13 TeV with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 35.9 fb−1 . The ZZ production cross section, σ(pp→ZZ)=17.2±0.5(stat)±0.7(syst)±0.4(theo)±0.4(lumi) pb , measured using events with two opposite-sign, same-flavor lepton pairs produced in the mass region 60<mℓ+ℓ−<120GeV , is consistent with standard model predictions. Differential cross sections are measured and are well described by the theoretical predictions. The Z boson branching fraction to four leptons is measured to be B(Z→4ℓ)=4.83+0.23−0.22(stat)+0.32−0.29(syst)±0.08(theo)±0.12(lumi)×10−6 for events with a four-lepton invariant mass in the range 80<m4ℓ<100GeV and a dilepton mass mℓℓ>4GeV for all opposite-sign, same-flavor lepton pairs. The results agree with standard model predictions. The invariant mass distribution of the four-lepton system is used to set limits on anomalous ZZZ and ZZ γ couplings at 95% confidence level: −0.0012<fZ4<0.0010 , −0.0010<fZ5<0.0013 , −0.0012<fγ4<0.0013 , −0.0012<fγ5<0.0013 .

Measurements of the pp -> ZZ production cross section and the Z -> 4l branching fraction, and constraints on anomalous triple gauge couplings at root s = 13 TeV (vol 78, 165, 2018) / Sirunyan, A.M., Tumasyan, A., Adam, W., Ambrogi, F., Asilar, E., Bergauer, T., Brandstetter, J., Brondolin, E., Dragicevic, M., Eroe, J., Flechl, M., Friedl, M., Fruehwirth, R., Ghete, V.M., Grossmann, J., Hrubec, J., Jeitler, M., Koenig, A., Krammer, N., Kraetschmer, I., et al.. - In: THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS. - ISSN 1434-6044. - STAMPA. - 78:6(2018). [10.1140/epjc/s10052-018-5769-1]

Measurements of the pp -> ZZ production cross section and the Z -> 4l branching fraction, and constraints on anomalous triple gauge couplings at root s = 13 TeV (vol 78, 165, 2018)

Creanza, D.;De Filippis, N.;Iaselli, G.;Maggi, G.;Pugliese, G.;
2018

Abstract

Four-lepton production in proton-proton collisions, pp→(Z/γ∗)(Z/γ∗)→4ℓ , where ℓ=e or μ , is studied at a center-of-mass energy of 13 TeV with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 35.9 fb−1 . The ZZ production cross section, σ(pp→ZZ)=17.2±0.5(stat)±0.7(syst)±0.4(theo)±0.4(lumi) pb , measured using events with two opposite-sign, same-flavor lepton pairs produced in the mass region 604GeV for all opposite-sign, same-flavor lepton pairs. The results agree with standard model predictions. The invariant mass distribution of the four-lepton system is used to set limits on anomalous ZZZ and ZZ γ couplings at 95% confidence level: −0.0012
2018
https://link.springer.com/article/10.1140%2Fepjc%2Fs10052-018-5769-1
https://link.springer.com/article/10.1140%2Fepjc%2Fs10052-018-5567-9
Measurements of the pp -> ZZ production cross section and the Z -> 4l branching fraction, and constraints on anomalous triple gauge couplings at root s = 13 TeV (vol 78, 165, 2018) / Sirunyan, A.M., Tumasyan, A., Adam, W., Ambrogi, F., Asilar, E., Bergauer, T., Brandstetter, J., Brondolin, E., Dragicevic, M., Eroe, J., Flechl, M., Friedl, M., Fruehwirth, R., Ghete, V.M., Grossmann, J., Hrubec, J., Jeitler, M., Koenig, A., Krammer, N., Kraetschmer, I., et al.. - In: THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS. - ISSN 1434-6044. - STAMPA. - 78:6(2018). [10.1140/epjc/s10052-018-5769-1]
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11589/138588
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