Probing p p WWW production and anomalous quartic gauge couplings at CERN LHC and future collider

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1 Outline Motivation and Introduction WWW production Anomalous Quartic Gauge Couplings Summary Probing p p WWW production and anomalous quartic gauge couplings at CERN LHC and future collider Yiwen Wen,Daneng Yang, Huilin Qu, Qishu Yan and Qiang Li Peking University, University of Chinese Academy of Sciences April 11, TeV future collider simulation meeting 1 / 22

2 1 Motivation and Introduction Motivation Introduction 2 WWW production Event selection Results 3 Anomalous Quartic Gauge Couplings EFT Operators Selections Results 4 Summary Summary 2 / 22

3 Motivation and Introduction 3 / 22

4 Motivation Triple gauge bosons production including WWW probably will be discovered at 2015 LHC restart and future collider. The first detail study of massive triple gauge bosons production QGC can be sensitive to new physics effects. We study the aqgc of W + W W + W vertice and give a new constraints on the strength of couplings. 4 / 22

5 Introduction We study the p p WWW production with pure leptonic decay channel in 14 TeV and 100 TeV. The final state would be 3 leptons and MET. Hence, the main backgrounds are: WZ, ttw, ZZ, ttz, WWZ. 5 / 22

6 Feynmann Diagrams (a) With TGC (b) With (anomalous) QGC (c) With higgs coupling (d) QED Radiations from WW 6 / 22

7 Simulation framework 7 / 22

8 WWW production 8 / 22

9 Preselection In MadGraph before generating events, we required that: 1 P tl > 10GeV 2 MET>20GeV 3 dr ll = η l < 2.5 Note that in the background ZZ, ttz, WWZ production process, one lepton is missing. Hence we don t set cut on leptons in this sample generation. 9 / 22

10 Delphes Card In detector simulation, for 14 TeV, we use default CMS setup. As to 100 TeV, we use Snowmass setup. Snowmass 1 PileUp Merger:Mean PileUp Electron efficiency: P T 10 0% in η 1.5, P T > 10 98% in 1.5 η 2.5, P T > 10 90% in η 2.5, P T > 10 0% 3 Muon efficiency: P T 10 0% in η 1.5, P T > 10 99% in 1.5 η 2.4, P T > 10 97% in η 2.4, P T > 10 0% 4 b-tagging:efficiency formula as function of η and P t 10 / 22

11 Event selection of 100TeV collider Cut flow: 1 Exactly 3 leptons, P T > 15GeV,η <2.4 2 MET>50GeV (25 in 14TeV LHC) 3 Veto b-jet P t > 50 GeV 4 There 2 schemes of leptons selection, more about this later 5 M ll > 12GeV 6 Transverse Mass MT>200GeV 7 R lj, R ll > leading lepton P T > 35GeV Note that: MT = ( Pt 2 lll + m 2 lll + MET 2 + m 2 lll ) 2 ( Pt lll + MET ) 2 11 / 22

12 Scheme 1 Using 2 different analysis scripts, only cut 4 is different. Scheme 1 Require mass difference between the invariant mass of the same flavor opposite sign lepton pairs and mass of Z is larger than 15 GeV. Namely, Mll OS M z > 15GeV 12 / 22

13 Scheme 2 Scheme 2 Class 2 types of lepton combination Type 1: 3 electrons, 3 muons, mu+ mu- e, e+ e- mu Type 2: mu+(-) mu+(-) e, e+(-) e+(-) mu Drop all the Type 1 event since only the signal process contains Type 2 event. 13 / 22

14 14 TeV results Events XS[fb] cut-based BDT Pileup 0 Pileup 50 Pileup 140 Pileup 0 s1 s2 s1 s2 s1 s2 s1 WWW WZ t tw ZZ t tz WWZ significance Table: Cut flow at the LHC with s = 14 TeV and integrated luminosity of 100 fb / 22

15 100 TeV results Events XS[fb] cut-based Pileup 50 Pileup 140 s1 s2 s1 s2 WWW WZ t tw ZZ t tz WWZ significance Table: Cut flow at future p p collider with s = 100 TeV and integrated luminosity of 3000 fb / 22

16 Anomalous Quartic Couplings of WWWW 16 / 22

17 Effective field theory(eft) Construct the effective Lagrangian of aqgc in a model independent way Still assuming the new physics keeps SU(2) L U(1) Y The Lagrangian can be expressed in non-linear or linear representation Since a Higgs was discovered, the linear one is more preferable. The lowest order of genuine linear representation EFT operator is dimension 8. The Lagrangian we are interested L = L SM + f j Λ 4 O j 17 / 22

18 L S,0, L S,1 and L T,0 L S,0 = f S0 Λ 4 [(D µφ) D ν Φ] [(D µ Φ) D ν Φ] L S,1 = f S1 Λ 4 [(D µφ) D µ Φ] [(D ν Φ) D ν Φ] L T,0 = f T 0 Λ 4 Tr[Ŵ µν Ŵ µν ] Tr[Ŵ αβ Ŵ αβ ] Where Φ is the Higgs doublet, D µ Φ = ( µ igwµ j σj 2 ig 1 B µ 2 )Φ and Ŵ µν j W µν j σj 2. And W µν i is the SU(2) L field strength and B µν is the U(1) Y one. 18 / 22

19 New Cuts to aqgc The aqgcs lead to excesses on hard tails. Modify selection cuts to separate the aqgc 1 (1) met > 350GeV. 2 (2) M T > 1000 GeV. 3 (3) leading lepton P T > 200 GeV. 19 / 22

20 Results The constraints on aqgc couplings are at 95%CL in 14 TeV LHC with 100 fb 1 Scheme 1: GeV -4 < f S0 /Λ 4 < GeV -4, (1) GeV -4 < f S1 /Λ 4 < GeV -4, (2) GeV -4 < f T 0 /Λ 4 < GeV -4, (3) Scheme 2: GeV -4 < f S0 /Λ 4 < GeV -4, (4) GeV -4 < f S1 /Λ 4 < GeV -4, (5) GeV -4 < f T 0 /Λ 4 < GeV -4, (6) 20 / 22

21 Comparison f S0 WWW VBF by Eboli SnowmassWWW [GeV 4 ] Λ 4 f S1 [GeV 4 ] Λ 4 f T 0 [GeV 4 ] Λ 4 Our results are presented at 95%CL with 100 fb in 5 σ with 100 fb 1 arxiv:hep-ph/ results are presented at 99% CL arxiv: results are at 5σ with 300 fb 1 21 / 22

22 Summary It reaches 1.2 σ to observe WWW production at 14 TeV LHC with 100 fb 1 We gave a better results on aqgc than Snowmass but less stringent than VBF 22 / 22