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

300 0 01 02 sm minimum 68 contour 95 contour 01 005

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Unformatted text preview: From Abazov et al., 2009g. TABLE XVIII. The most probable values with total uncertainties (statistical and systematic) at 68% C.L. for  , , and gZ along with observed 95% C.L. one-parameter limits on Á , , and ÁgZ 1 1 measured in 1:1 fbÀ1 of WW=WZ ! ‘jj events with ÃNP ¼ 2 TeV for the D0 analysis (Abazov et al., 2009g).   ¼  ¼ Z gZ 1 SUð2ÞL  Uð1ÞY symmetry Equal couplings þ0 26  ¼ 1:07À0::29 þ0 11  ¼ Z ¼ 1:04À0::11 þ0 06  ¼ 0:00À0::06 þ0 06  ¼ 0:00À0::06 þ0 09 gZ ¼ 1:04À0::09 1 95% C.L. SUð2ÞL  Uð1ÞY symmetry Equal couplings Á À0:44 < Á < 0:55 À0:16 < Á < 0:23  ¼  ¼ Z À0:10 <  < 0:11 À0:11 <  < 0:11 ÁgZ 1 À0:12 < ÁgZ < 0:20 1 68% C.L. Rev. Mod. Phys., Vol. 84, No. 4, October–December 2012 Hobbs, Neubauer, and Willenbrock: Tests of the standard electroweak model at . . . 0.15 ×103 DØ Run II, 1.1 fb-1 0.1 Events/0.2 radians λ Data EWK MJB Uncertainty 5 0.05 0 -0.05 SM Minimum 68% Contour 95% Contour -0.1 -0.15 1503 -0.3 -0.2 -0.1 4 3 2 1 0 0.1 0.2 0.3 0 ∆κ 0 1 ∆φ 2 jet 3 ET FIG. 39. The 68% C.L. and 95% C.L. two-parameter limits on the WW=ZWW coupling parameters Á and , in the equal couplings scenario and ÃNP ¼ 2 TeV for the D0 analysis. The dot indicates the most probable values of anomalous couplings from the twoparameter combined (electron þ muon) fit and the star marker denotes the SM prediction. From Abazov et al., 2009g. FIG. 40 (color online). Data compared with the sum of the predicted EW and multijet backgrounds for the Ájet variable in ET 6 the CDF analysis. The band represents the total systematic uncertainty on the background. The measured signal is included here in the EW contribution. From Aaltonen et al., 2009a. backgrounds to the diboson signal are W ð‘Þ þ jets, ZðÞ þ jets, and QCD multijet production. Other less significant " backgrounds include Zð‘‘Þ þ jets, tt, and single t-quark production. The majority of events are collected using an 6 inclusive ET trigger which requires ET > 45 GeV. In the 6 offline selection, events are required to have ET > 60 GeV 6 and exactly two reconstructed jets with ET > 25 GeV and j  j < 2 :0 . The shape and normalization of the multijet background are determined from the data. A tracking-based missing momentum vector pT , analogous to the calorimeter-based 6~ ET , is constructed from the vector sum of the transverse 6~ momenta of particles measured in the tracking system, and is largely uncorrelated to ET for events where jets are 6~ misreconstructed. In the absence of ET arising from mis6 measurement in the calorimeter, the ET and pT will be 6~ 6~ aligned in most events. At large values of ÁðET ; pT Þ, 6~ 6~ multijets are expected to be the dominant component of the data. The dijet mass shape and normalization for the multijet background that remains after the event selection are determined by selecting events with ÁðET ; pT Þ > 1:0 6~ 6~ and s...
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This document was uploaded on 09/28/2013.

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