Search for New Vector Boson from Minimal Higgless Model at CMS (based on FastSimulation) Bian J. G. Chen G. M. CMS group Institute of High Energy Physics Wang J.X. Theory division Qi Wei Zhang B. He H.J. Kuang Y.P. Qinghua University China, 2008 Jan 28

Introdution Signal Backgrounds Event selection Summary outline Introdution Signal Backgrounds Event selection Summary

Introduction If Higgs do not exist, the unitarity violation will apear in the scattering of massive gauge W±Z0→ W±Z0. To postpone unitarity, Higgsless models are proposed—new weakly coupled particles appear at the TeV scale. The typical ones are : 5d Higgsless models —tower of KK gauge states

Introduction(con’t) Minimal Higgsless model Hep-ph/0708.2588 predicts Just one pair of new W1 ,Z1 bosons as light as 400 GeV, in additon to SM weak boson W, Z0 and a vector- like heavy fermion. W1 and Z1 do not decay to lepton pairs Widths are narrow for 0.4 and 0.5 GeV mass

Introduction(con’t) Feynman Digram pp→W1qq’ →W±Z0qq’ Invariant mass distribution of W±Z0 for MW1=500GeV

Signal sample The generator authors are ones of Hep-ph/0708.2588 The process is fraction(sub 1)/fraction(sub 2) ≈2 The element matrix is calculated at tree level based on Minimal Higgsless Model.

Signal sample(con’t) the generator is interfaced with PYTHIA for the initial and final state radiation and parton hadronization. Then interfaced with CMSSW_1_6_9 for FastSimulation. The default pileup is taken into account.

Cross sections and Events for and Luminosity = 50/fb Signal sample(con’t) Cross sections and Events for and Luminosity = 50/fb CS EVTS Norm fact Preselection 550 1.576 1000 0.079 3μ:|η|<2.5 , pt>5 GeV, q, q’: |η|<7.0 , pt>5 GeV for parton like events 600 1.211 0.061 650 0.921 0.046 700 0.707 0.035 750 0.554 0.028 Mass units: GeV, CS units: fb, Norm=CS*LU/EVTS

Cross sections and Events for and Luminosity = 50/fb Signal sample(con’t) Cross sections and Events for and Luminosity = 50/fb CS EVTS Norm fact Preselection 550 0.918 1000 0.046 3μ:|η|<2.5 , pt>5 GeV, q, q’: |η|<7.0 , pt>5 GeV 600 0.682 0.034 650 0.525 0.026 700 0.384 0.019 750 0.294 0.015 Mass units: GeV, CS units: fb, Norm=CS*LU/EVTS

background samples The generators are PYTHIA. The detector simulation is CMSSW_1_6_9 FastSimulation. pp→ WZ0 →3 μν cross section is 97.33 fb pp→ WZ0qq’ →3 μνqq’ cross section is 6.21E-2 fb pp→ WW →2μ2ν cross section is 8.21E+2 fb

background samples(con’t) pp→ WW qq’ → 2μ2ν qq’ cross section = 1.42E+3 fb pp→ Z0 Z0 →4μ cross section =17.57fb pp→ Z0 Z0qq’ →4μqq’ cross section=5.48E-3fb pp→ ttbar →W+W-qq’ →2μqq’ cross section =5.73E+03 fb pp→ Zbb →2μbb cross section =1.54E+05 fb

background samples(con’t) Cross sections and Events set luminosity = 50/fb Process CS(fb) EVTS Norm fact Preselection WZ0 97.33 29550 0.164 Default Parameters of Pythia integrated with CMSSW WZ0qq’ 6.21E-2 1200 0.003 WW 8.21E+2 164750 0.249 WWqq’ 1.42E+3 283750 0.251 Z0Z0 17.57 83800 0.010 Z0Z0qq’ 5.48E-3 13570 2.E-6 ttbar 5.73E+3 574400 0.499 Z0bb 1.54E+5 8.25E+6 0.932

Events selection Cut 1: Number of muons is required to be 3, including Eachμis ParamGlobalMuons, and satisfies and within ∆R=sqrt(∆ η2+ ∆φ2) <0.3, Super Cluster energy <5 GeV.

Events selection(con’t) Cut 2: number of Jets≥1,Each Jet is iterativeCone5CaloJets, satisfies

Events selection(con’t) Cut 2: number of isolated Jets≥1(con’t)

Events selection(con’t) Cut 2: number of jets≥1(con’t)

Events selection(con’t) Cut 3: Highest momentum of 3μ>150 GeV.

Events selection(con’t) Cut 3: Highest p of 3μ>150 GeV(con’t)

Events selection(con’t) Cut 3: Highest p of 3μ>150 GeV(con’t)

Events selection(con’t) Cut 4:scalar sum of 3μPt

Events selection(con’t) Cut 4:scalar sum of 3μPt (con’t)

Events selection(con’t) Cut 4:scalar sum of 3μPt (con’t)

Events selection(con’t) Cut 5: |mz0 -91.17|< 15 GeV, maximal momentum of 2μ> 70 GeV

Events selection(con’t) Cut 5: |mz0 -91.17|< 15 GeV,maximal momentum of 2μ> 70 GeV (con’t)

Events selection(con’t) Cut 5: |mz0 -91.17|< 15 GeV,maximal momentum of 2μ> 70 GeV(con’t)

Events selection(con’t) Cut 6: 0<MtW< 340 GeV

Events selection(con’t) Cut 6: 0<MtW< 340 GeV(con’t)

Events selection(con’t) Cut 6: 0<MtW< 340 GeV (con’t)

Events selection(con’t) Cut 7: maximal p of jets>200 GeV

Events selection(con’t) Cut 7: maximal p of jets>200 GeV (con’t)

Events selection(con’t) Cut 7: maximal p of jets>200 GeV (con’t)

Cut 8: 540<Mhwz<1600 GeV Which is different from transverse mass Events selection Cut 8: 540<Mhwz<1600 GeV Which is different from transverse mass

Events selection(con’t) Cut 8: 540<Mhwz<1600 GeV (con’t) Mhwz Mtwz

Events selection(con’t) Cut 8: 540<Mhwz<1600 GeV (con’t)

Events selection(con’t) Cut 8: 540<Mhwz<1600 GeV(con’t)

Events selection(con’t) Final Events and Significance Significance =sqrt(2lnQ),Q=(1+Ns/Nb)Nbexp(-Nb), Ns=19.4,Nb=8.3 for W1 mass=700 GeV Significance: 5.3 for luminosity=50/fb, i.e. Significance: 5. for luminosity=44.7/fb

Events selection(con’t) Efficiency of cuts , here W1 mass = 700 GeV PROCESS CR*50/fb Num of μs= 3 Jets≥1 Maxi p of 3μ>150 W1+ 35.4 21.9(61.90%) 21.4(60.60%) 21.3(60.40%) W1- 19.2 11.9(61.70%) 11.5(59.70%) 11.3(58.80%) WZ 4858.5 1510(31.08%) 423(8.69%) 241.3(4.96%) WZqq’ 3.1 1.6(50.50%) 1.5(47.92%) 0.97(31.17%) ZZ 878.5 204(23.23%) 54.7(6.23%) 31.82(3.62%) ZZqq’ 0.27 0.09(32.07%) 0.08(29.73%) 0.06(20.13%) WW 41035 26.7(0.06%) 9.7(0.02%) 6.0(0.01%) WWqq’ 71200 125 (0.18%) 98.9(0.14%) 43.7(0.06%) ttbar 286675 12140(4.24%) 9727(3.39%) 4312(1.50%) Z0bb 7689250 50583(0.66%) 10401(0.14%) 3173(0.04%) Sig Background

Events selection(con’t) Efficiency of cuts (con’t) PROCESS sum of 3μpt> 300 |mZ0-91.17| <15 Mtw<340 W1+ 18.5(52.40%) 15.9(44.9%) 15.7(44.3%) W1- 10.2(52.90%) 8.9(46.30%) 8.8(45.8%) WZ 29.4(0.61%) 23.9(0.49%) 23.7(0.49%) WZqq’ 0.22(7.08%) 0.20(6.50%) ZZ 3.4(0.39%) 2.6(0.29%) 2.5(0.29%) ZZqq’ 0.01(2.92%) 0.007(2.66%) 0.007(2.63%) WW 1.0(0.002%) 0(0.00%) WWqq’ 0.7(0.001%) ttbar 192.7(0.07%) 31.9(0.010%) 31.4(0.01%) Z0bb 1.76(0.23E-4%) 0.89(0.11E-4%) Sig Background

Events selection(con’t) Efficiency of cuts (con’t) PROCESS Maxi p of Jets > 200 540<mw1<1600 Final Events W1+ 14.3(40.60%) 12.4(35.10%) 19.4 W1- 7.8(40.60%) 7.0(36.6%) WZ 13.5(0.28%) 5.9(0.12%) 8.3 WZqq’ 0.19(6.08%) 0.05(1.75%) ZZ 1.3(0.15%) 0.4(0.046%) ZZqq’ 0.007(2.49%) 0.003(0.98%) WW 0(0.00%) WWqq’ ttbar 21.5(0.007%) 2.0(0.0006%) Z0bb Sig Background

Events selection M (GeV) Signal Bg Signif Luminosity for5σ(fb-1) 550 Events left and Significance as function of W1mass for luminosity of 50/fb M (GeV) Signal Bg Signif Luminosity for5σ(fb-1) 550 16.7+10.0 8.3 6.9 26.4 600 16.8+11.0 7.1 24.7 650 15.4+8.9 6.4 30.8 700 12.4+7.0 5.3 44.7 750 10.9+5.3 4.5 60.6

Summary We study discovery potential of new charged boson W1 based on FastSimulation If W1 mass is 600 GeV, We can find 5 sigma Signal with data of 24.7/fb . If W1 mass is 750 GeV, We can find 5 sigma Signal with data of 60.6/fb