A measurement is performed of the cross section of top quark pair production in association with a W or Z boson using proton-proton collisions at a center-of-mass energy of 13TeV at the LHC. The data sample corresponds to an integrated luminosity of 35.9 fb(-1), collected by the CMS experiment in 2016. The measurement is performed in the same-sign dilepton, three-and four-lepton final states. The production cross sections are measured to be sigma(t (t) over barW) = 0.77(-0.11)(+0.12)(stat)(-0.12)(+0.13) pb and sigma(t (t) over barZ) = 0.99(-0.08)(+0.09) (stat)(-0.10)(+0.12) (syst) pb. The expected (observed) signal signi fi cance for the sigma(t (t) over barW production in same-sign dilepton channel is found to be 4.5 (5.3) standard deviations, while for the t (t) over barZ production in three- and four-lepton channels both the expected and the observed signi fi cances are found to be in excess of 5 standard deviations. The results are in agreement with the standard model predictions and are used to constrain the Wilson coe ffi cients for eight dimension-six operators describing new interactions that would modify t (t) over barW and t (t) over barZ production.
Measurement of the cross section for top quark pair production in association with a W or Z boson in proton-proton collisions at √ s=13 TeV
Ciocci, M. A.;Fedi, G.;Grippo, M. T.;Messineo, A.;Rizzi, A.;Tonelli, G.;Cipriani, M.;Bianchini, L.;Donato, S.;Marini, A. C.;
2018-01-01
Abstract
A measurement is performed of the cross section of top quark pair production in association with a W or Z boson using proton-proton collisions at a center-of-mass energy of 13TeV at the LHC. The data sample corresponds to an integrated luminosity of 35.9 fb(-1), collected by the CMS experiment in 2016. The measurement is performed in the same-sign dilepton, three-and four-lepton final states. The production cross sections are measured to be sigma(t (t) over barW) = 0.77(-0.11)(+0.12)(stat)(-0.12)(+0.13) pb and sigma(t (t) over barZ) = 0.99(-0.08)(+0.09) (stat)(-0.10)(+0.12) (syst) pb. The expected (observed) signal signi fi cance for the sigma(t (t) over barW production in same-sign dilepton channel is found to be 4.5 (5.3) standard deviations, while for the t (t) over barZ production in three- and four-lepton channels both the expected and the observed signi fi cances are found to be in excess of 5 standard deviations. The results are in agreement with the standard model predictions and are used to constrain the Wilson coe ffi cients for eight dimension-six operators describing new interactions that would modify t (t) over barW and t (t) over barZ production.File | Dimensione | Formato | |
---|---|---|---|
JHEP_08_2018_011.pdf
accesso aperto
Tipologia:
Versione finale editoriale
Licenza:
Creative commons
Dimensione
1.55 MB
Formato
Adobe PDF
|
1.55 MB | Adobe PDF | Visualizza/Apri |
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.