Publication Date:
2013-03-01
Description:
A measurement of the ZZ production cross section in proton-proton collisions at $ sqrt{s}=7 $ TeV using data recorded by the ATLAS experiment at the Large Hadron Collider is presented. In a data sample corresponding to an integrated luminosity of 4.6 fb−1 collected in 2011, events are selected that are consistent either with two Z bosons decaying to electrons or muons or with one Z boson decaying to electrons or muons and a second Z boson decaying to neutrinos. The ZZ (*) → ℓ + ℓ − ℓ ′+ ℓ ′− and $ ZZo {ell^{+}}{ell^{-}}
u overline{
u} $ cross sections are measured in restricted phase-space regions. These results are then used to derive the total cross section for ZZ events produced with both Z bosons in the mass range 66 to 116 GeV, $ sigma_{ZZ}^{mathrm{tot}} = 6.7 pm 0.7;,left( {mathrm{stat}.}
ight);;_{-0.3}^{+0.4};,left( {mathrm{syst}.}
ight) pm 0.3;,left( {mathrm{lumi}.}
ight) $ pb, which is consistent with the Standard Model prediction of $ 5.89_{-0.18}^{+0.22 } $ pb calculated at next-to-leading order in QCD. The normalized differential cross sections in bins of various kinematic variables are presented. Finally, the differential event yield as a function of the transverse momentum of the leading Z boson is used to set limits on anomalous neutral triple gauge boson couplings in ZZ production.
Print ISSN:
1126-6708
Electronic ISSN:
1029-8479
Topics:
Physics
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