CSCresultsofWZanalysisatATLASSimpiecutsStraightcutsdatasetstableMCsamplePre-selectionStraight cutsProcess(sig)sL(fb-1)#tol evets#eff_pre#(1fb-1)eff_sim#(1fb-1)eeeeemmmemmm2.826.4437.4123.194.759.19ZW-->Il (I=e,m)147750554.442074314.0393%1285961.9920%3.696.808.28313.9450.51949230.2411.47ZW+ -> II (I=e,m)1336741585711.8624%59.8600%total868.3887.9253.436.51111.5514.7220.66##Process(bkg)tol_evetsL(fb-1)effpre#(1fb-1)eff_sim#(1fb-1)eeeeemmmemmm0043.7950.110.0200.02wW->mu+mu570000.0088%120.0000%ZZ_4I49250739.497.442.680.090.740.131.72198235.9710%551011.1675%01.1720.18099974211.13130.090.09Zgamma_l0.0013%15.3846%0000.549.220005T1.McAtNLO6012499000.0020%0.0000%0000.749.48000T1_McAtNLO_60434045070.0021%0.0000%0000000.3339.041984500.0015%0.0000%Acerttbar->I+x2000.744155.092.691.341.34DY(81-100)_2144959980.0009%4.8780%204.95397.870.4000.42996413Zjet(10-20)_2mu0.0013%5.1282%5.132.9250.97001995792150.390.58Zjet(20-40)_2mu0.0008%33.3333%006.6511517.2960.900.1511897930.0097%5.2174%0.75Zjet(40-80)_2mu200010.81383.520.193978560.18Zjet(80-120)_2mu0.0096%5.2632%0000-%00others0.0000%1033.19105.923.98total8.021.520.741.76S/B0.840.83S/B6.664.2815.618.345.19Whatfollowsaredistributionsof signal and somemainbackgroundsscaledbycrosssectionsandnormalizedto 1 fb-1
Cunfeng Feng Single top meetingFCPPL workshop, Wuhan 6 CSC results of WZ analysis at ATLAS
Prospectfor1/fb:eventyield,cross section precisiona 10% measurement!large roomforeeeeemmmemmmoptimizationWZ20.225.629.747.6zZ2.62.7logLikelihood3.94.5-11.8ZPhoton29.808.10-120.70.70ttbar6.7-12.21.7WW0.10.10-124Total3.540.812.84.5-12.6background-12.81338.7%21.1%22.0%15.2%o/o(stat)Measured o*BR = 178.512522.4%Aa/o (total)56.4%24.6%16.8%13.4160170190180064-channelcombination:uncertaintycorrelationsbasedonv14MCsamplesaccountedforCunfeng FengSingletopmeetingFCPPLworksho
Cunfeng Feng Single top meetingFCPPL workshop, Wuhan 7 Prospect for 1/fb: event yield, cross section precision eee eem mme mmm WZ 20.2 25.6 29.7 47.6 ZZ 2.6 2.7 3.9 4.5 ZPhoton 29.8 0 8.1 0 ttbar 6.7 0.7 0.7 0 WW 1.7 0.1 0.1 0 Total background 40.8 3.5 12.8 4.5 Δσ/σ (stat) 38.7% 21.1% 22.0% 15.2% Δσ/σ (total) 56.4% 22.4% 24.6% 16.8% 4-channel combination: uncertainty correlations accounted for. Measured *BR = 178.5−17.5 +19.5 a 10% measurement! large room for optimization based on v14 MC samples
Ttbarcrosssectionm1000CDFCombinationMtop=172.5itDoCombinationMtop=170GeVbLHC10TeV@200pb-1ExpectationsLHC10TeV@200pb1Expectations(noLumi800LHC14TeV@100pb1Expectations(CSC)NLO+NNLLMtop=172.5NLO+NNLLScaleUncertaintyNLO(Pp)Mtop=172.5NLO（pP)Mtop=172.560010400450oue[hep-ph/0204244]ees200larX:0907.252723TC0Fnote9913)1.52.51[arXiv:0903.5525]Deanoo101214?TtbarTotal:160pbVs[TeV]Semi-lepton:48pbDi-lepton:8pbCunfeng FengSingletopmeetingFCPPLworkshop-
Cunfeng Feng Single top meetingFCPPL workshop, Wuhan 8 Ttbar cross section Ttbar Total:160pb Semi-lepton: 48pb Di-lepton: 8pb
Ttbarsemi-lepton@10TeV(200pb-1)EventselectionExactlyonelepton(electronormuon)withpT>20GeVMissing ET>20 GeV.AtleastfourjetswithpT>20GeVat least three jetsNumbersof Selected EventshavepT>40GeV.ElectronAnalysisMuonAnalysisSampledefault+Mw-cutdefault+Mw-cutti2600128631441584No b-jet tag usedW+jets130544862817662108122798singletop4349148144Z-ll +jets5101116hadronicti710Wbb2132714ww1163152WZZZ0.20.50.40.22600128631441584SignalATL-PHYS-PUB-2009-087598799Background17152199S/B2.1IS142.0Cunfeng Feng9SingletopmeetingFCPPLworkshop
Cunfeng Feng Single top meetingFCPPL workshop, Wuhan 9 Ttbar semi-lepton @10TeV (200pb-1 ) Event selection • Exactly one lepton (electron or muon) with pT> 20 GeV. • Missing ET > 20 GeV. • At least four jets with pT> 20 GeV. • at least three jets have pT> 40 GeV. No b-jet tag used ATL-PHYS-PUB-2009-087
Ttbarsemi-leptonic cross sectionPTTTTEn180ATLASPreliminaryATLASPreliminary250(b)(a)160SimulationSimulationetbarbar200140lother福other山120singletsinglet150W+jetsW+jets10010100WmcutCut and countT40501-20OCOE5010015020025030035040045050050100150200250300350400450500O0M-[GeV]M.[GeV]A90ATLASPreliminaryATLASPreliminary100SimulationSimulation80--70?ElectronChannelMuon Channel60Top mass fit-L-200pb1L-200pb50601402TH40Electron30Mu202010ITTrOEOL250350250100150200300100150200300350M[Gev]M[GeV]Cunfeng Feng10SingletopmeetingFCPPLworkshop
Cunfeng Feng Single top meetingFCPPL workshop, Wuhan 10 Ttbar semi-leptonic cross section Wm cut Cut and count Top mass fit Electron Mu