RevModPhys.84.1477】Tests of the standard electroweak model at the energy frontier

They are shown in fig 39 rev mod phys vol 84 no 4

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Unformatted text preview: dropping the requirement of a reconstructed charged lepton and instead looking at the ET þ jets final state. This 6 approach includes an additional contribution from Z !  over the WW=WZ ! ‘jj mode so that it measures WW þ WZ þ ZZ production and allows for an event with a diboson decay to be accepted even if one or more charged leptons fail a selection cut. The experimental challenge is that this mode requires a tighter ET cut as compared to WW=WZ ! ‘jj 6 TABLE XVII. Allowed anomalous coupling ranges for à ¼ 1:5 TeV at 95% C.L., fixing the other coupling to the SM value and assuming equal WW and WWZ couplings for the CDF analysis (Aaltonen et al., 2007a).  ‘jj ‘ a Combined a Acosta et al., 2005b. Á (À 0:28, 0.28) (À 0:21, 0.19) (À 0:18, 0.17) (À 0:50, 0.43) (À 0:74, 0.73) (À 0:46, 0.39) Hobbs, Neubauer, and Willenbrock: Tests of the standard electroweak model at . . . Events / 10 GeV/c (a) DØ Run II, 1.1 fb-1 104 Data Diboson Signal W+jets Z+jets Top Multijet 103 102 0.15 -1 DØ Run II, 1.1 fb (a) 0.1 0.05 λ 1502 0 -0.05 10 SM Minimum 68% Contour 95% Contour -0.1 -0.15 1 0 50 100 150 200 250 -0.6 300 -0.4 -0.2 Dijet pT (GeV/c) 4 Data - (SM Sig+Bkgd) 2 0.4 0.6 0.2 95% CL for κ 95% CL for λ 3 0.2 -1 DØ Run II, 1.1 fb (b) DØ Run II, 1.1 fb-1 0.1 1 ∆ gZ Events / (stat. ⊕ syst.) (b) 0 ∆ κγ 1 0 0 -0.1 SM Minimum 68% Contour 95% Contour -1 -0.2 -2 -3 0 -0.6 50 100 150 200 250 -0.4 -0.2 0 Dijet pT (GeV) 0.4 0.6 -1 DØ Run II, 1.1 fb (c) 0.2 0.1 1 ∆ gZ FIG. 37 (color online). For the D0 analysis, the (a) dijet pT distribution of combined (electron þ muon) channels for data and SM predictions following the fit of simulated events to data, and (b) the difference between data and simulation divided by the uncertainty (statistical and systematic) for the dijet pT distribution. Also shown are the simulated signals for anomalous couplings corresponding to the 95% C.L. limits for Á and  in the LEP parametrization scenario. The full error bars on the data points reflect the total (statistical and systematic) uncertainty, with the ticks indicating the contribution due only to the statistical uncertainty. From Abazov et al., 2009g. 0.2 ∆ κγ 300 0 -0.1 -0.2 SM Minimum 68% Contour 95% Contour -0.1 -0.05 0 0.05 0.1 λ and a better overall understanding of high reconstructed ET 6 tails from low true ET events with a large cross section such 6 as QCD multijets. R The CDF Collaboration uses Ldt ¼ 3:5 fbÀ1 to search for the production of heavy vector boson pairs (VV , V ¼ W , Z) where one boson decays to a dijet final state (Aaltonen et al., 2009a). The most significant FIG. 38. The 68% C.L. and 95% C.L. two-parameter limits on the WW=ZWW coupling parameters Á , , and ÁgZ , in the LEP 1 parametrization scenario and ÃNP ¼ 2 TeV for the D0 analysis. The dots indicate the most probable values of anomalous couplings from the two-parameter combined (electron þ muon) fit and the star markers denote the SM prediction....
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This document was uploaded on 09/28/2013.

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