Measurements of the p p → Z Z production cross section and the Z → 4 ℓ branching fraction, and constraints on anomalous triple gauge couplings at √s=13TeV

Date Issued
01-02-2018
Author(s)
Sirunyan, A. M.
Tumasyan, A.
Adam, W.
Ambrogi, F.
Asilar, E.
Bergauer, T.
Brandstetter, J.
Brondolin, E.
Dragicevic, M.
Erö, J.
Flechl, M.
Friedl, M.
Frühwirth, R.
Ghete, V. M.
Grossmann, J.
Hrubec, J.
Jeitler, M.
König, A.
Krammer, N.
Krätschmer, I.
Liko, D.
Madlener, T.
Mikulec, I.
Pree, E.
Rabady, D.
Rad, N.
Rohringer, H.
Schieck, J.
Schöfbeck, R.
Spanring, M.
Spitzbart, D.
Waltenberger, W.
Wittmann, J.
Wulz, C. E.
Zarucki, M.
Chekhovsky, V.
Mossolov, V.
Gonzalez, J. Suarez
De Wolf, E. A.
Di Croce, D.
Janssen, X.
Lauwers, J.
Van De Klundert, M.
Van Haevermaet, H.
Van Mechelen, P.
Van Remortel, N.
Zeid, S. Abu
Blekman, F.
D’Hondt, J.
De Bruyn, I.
De Clercq, J.
Deroover, K.
Flouris, G.
Lontkovskyi, D.
Lowette, S.
Moortgat, S.
Moreels, L.
Python, Q.
Skovpen, K.
Tavernier, S.
Van Doninck, W.
Van Mulders, P.
Van Parijs, I.
Brun, H.
Clerbaux, B.
De Lentdecker, G.
Delannoy, H.
Fasanella, G.
Favart, L.
Goldouzian, R.
Grebenyuk, A.
Karapostoli, G.
Lenzi, T.
Luetic, J.
Maerschalk, T.
Marinov, A.
Randle-conde, A.
Seva, T.
Velde, C. Vander
Vanlaer, P.
Vannerom, D.
Yonamine, R.
Zenoni, F.
Zhang, F.
Cimmino, A.
Cornelis, T.
Dobur, D.
Fagot, A.
Gul, M.
Khvastunov, I.
Poyraz, D.
Roskas, C.
Salva, S.
Tytgat, M.
Verbeke, W.
Zaganidis, N.
Bakhshiansohi, H.
Bondu, O.
Brochet, S.
Bruno, G.
DOI
Abstract
Four-lepton production in proton-proton collisions, p p → (Z / γ∗) (Z / γ∗) → 4 ℓ, where ℓ= e or μ, is studied at a center-of-mass energy of 13TeV with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 35.9fb-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=4.8±0.2(stat)±0.2(syst)±0.1(theo)±0.1(lumi)×10-6 for events with a four-lepton invariant mass in the range 80<m4ℓ<100GeV and a dilepton mass m4GeV 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 ZZγ couplings at 95% confidence level: -0.0012<f4Z<0.0010, -0.0010<f5Z<0.0013, -0.0012<f4γ<0.0013, -0.0012<f5γ<0.0013.
Volume
78