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Higgs branching ratios study for DBD

Higgs branching ratios study for DBD. ILC physics WG general meeting Jan. 12 2013 H. Ono (NDU). Higgs BR study in DBD. Detailed Baseline Design document publication is on- going Physics chapter Demonstrate performance of Higgs measurement in ILC

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Higgs branching ratios study for DBD

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  1. Higgs branching ratios study for DBD ILC physics WG general meeting Jan. 12 2013 H. Ono (NDU) ILC physics WG general meeting

  2. Higgs BR study in DBD • Detailed Baseline Design document publication is on-going • Physics chapter • Demonstrate performance of Higgs measurement in ILC • 250 to 1 TeV with possible decay channels • Update hWW* analysis at 250 GeV (rightleft beam pol) • Detector chapter (detector benchmarking process) • vvh @ 1 TeV decaying into bb, cc, gg, WW* • sigma*BRs are evaluated ILC physics WG general meeting

  3. Higgs BR study at 1 TeV (DBD) Higgs mainly produced via e+e-νeνeh (WW-fusion) hbb, cc, gg (two jets) hWW* (four jets via hadronic decay) hμμ (dilepton)C. Constantino (KEK) Ecm=1 TeV Luminosity: L=1 ab-1 (500 fb-1 both pol.) Beam polarization P(e-, e+)=(0.8, 0.2) γγhadron BG is overlaid (4 event/BX) Larger cross section than Zh@250 GeV Statistical gain (xsec and luminosity)Measure smaller BR channels ILC physics WG general meeting

  4. ΥΥhadron background treatment Beam related particle (4.1 event/BX) is treated with kt jet clustering (commonly used in hadron collider study) Higgs dijet rec. with γγhadron BG Jet reconstruction procedure Apply kt two jet clustering Use only jet associated PFOs Reapply flavor tagging and jet clustering with LCFIPlus Optimize R parameter used in ktalgorithm Select R=1.1 for 2 jet reconstruction Check Higgs reconstruction and BG reduction with γγ BG overlay ILC physics WG general meeting

  5. Cuts for hbb, cc, gg channel @ 1 TeV Visible energy: 40 < Evis < 450 GeV Transverse momentum: PT>20 GeV Longitudinal momentum: |PZ|<400 GeV # of PFOs: NPFOs>20 |cosθh|<0.98 Dijet mass: 110<Mh<150 GeV After all cuts, flavor template fitting is applied ILC physics WG general meeting

  6. hbb, cc, ggtemplate fitting analysis After the cuts, prepare flavor templates of signals and BGs rxx=σBR/σBRSM(hxx) Ndata=Σrxx*Ntemplate(hxx)+NBG (rxxis a fitted parameter) Ndata is fluctuated wit Poisson 5,000 times of Toy MC is applied to evaluate the accuracy of σBR BG templates Data hothers SM BGs hgg hbb hcc Signal templates ILC physics WG general meeting

  7. hbb, cc, gghadronic channel @ 1 TeV Flavor template for hbb, cc, gg and others are prepared Template fitting is performed to evaluate accuracy of σBR Fitted rbb, rcc, rgg Higgs mass with B-tagging (hbb) rcc rbb rgg L=500 fb-1and 1 ab-1P(-0.8, +0.2) ILC physics WG general meeting

  8. hWW* channel @ 1 TeV hWW* (one on-shell W) from Higgs decay hWW*qqqq fully hadronic decay channel is considered Apply forced four jet clusteringwithkt jet clustering (R=1.1) Apply flavor tag forjet associated particleswith LCFIPlus Jet clustering and paring for W1, W2(W1 is on-shell with J1, J2) Select best candidate with minimizing χ2 W2 h W1 L=500 fb-1, 1 ab-1 (e-,e+)=(-0.8, +0.2) ILC physics WG general meeting

  9. hWW* background reduction Npfos -Log10Y34 -Log10Y45 Remove leptonic Remove di-jets Off-shell W mass Btag sum On-shell W mass Remove hbb ILC physics WG general meeting

  10. hWW*4j reconstruction L=500 fb-1 (e-,e+)=(-0.8, +0.2) Significance=46.2 ΔσBR/σBR = 2.2% ILC physics WG general meeting

  11. Beam polarization effectP(e-,e+)=PL(-0.8, +0.2) and PR(+0.8, -0.2) eL(-0.8,+0.2) eR(+0.8,-0.2) Decrease eevvh WW-fusion production process Statistical gain at higher energy Same cut and strategy are applied for right-handed case eR(+0.8, -0.2) ILC physics WG general meeting

  12. Summary of Higgs BR study at 1 TeV Ecm=1 TeV, L=500 fb-1, and 1 ab-1 (e-, e+)=(-0.8, +0.2), Mh=125 GeV Left/Right-handed combined Left-handed only Left-handed beam polarization run is suitable at 1 TeVfor Higgs analysis point of view ILC physics WG general meeting

  13. hWW* at 250 GeV ILC physics WG general meeting

  14. HWW* study @ 250 GeV Ecm=250 GeV, L=250 fb-1, Mh=120 GeV (LOI samples) Previous study only concerning right-handed polarization Check Left-handed beam polarization case to keep consistency with other channels P(-0.8, +0.3) @ 250 GeV ZhqqWW*qq+lvqq ZhvvWW*vv+qqqq W1 W1 Z H H Z W2 W2 4 jet final state lepton + 4 jet final state ILC physics WG general meeting

  15. 1. ZhvvWW*vv+qqqq@ 250 GeV, L=250 fb-1, Mh=120 GeV Apply forced four-jets clustering Require one on-shell W and4 jets consistent with Higgs Minimum c2 pair as best candidate W1 H Z Main background Hbb, WW, ZZ W2 4 jet final state ILC physics WG general meeting

  16. Cut variablesZhvvWW*vv+qqqq • 115<Evis<150 GeV(vvhchannel) • 20<Pt<90GeV • |Pl|<60 GeV • 85<Missing mass<150 GeV(Mmiss~MZ) • Nchdtrk>20 (4 jet finale state) • ConeEjet/Ejet<0.9 (Removeisolatedleptons) • Sum(WjBag)<1.0 (hbbsuppression) • b-likeness2j<0.45 (hbbsuppression) • Sum(Y34_j)<10(hotherssuppression) • 65<Mw1<95GeV (On-shell W mass) • 110<Mh<130GeV ILC physics WG general meeting

  17. Cut variables to suppress BGs ConeEjet/Ejet Btag sum for 4j Cone angle = 5 degree -Log10(Y34) sum for 4j Ejet ConeE<Ejet ConeE coneE~Ejet leptonic channel ILC physics WG general meeting

  18. Reconstructed Higgs massZhvvWW*vv+qqqq Ecm=250 GeV, L=250 fb-1, Mh=120 GeV eR(+0.8, -0.3) eL(-0.8, +0.3) Higgs mass (GeV) Higgs mass (GeV) Signal significance=8.2 ΔσBR/σBR=12.3% Signal significance=10.6 ΔσBR/σBR=9.5% ILC physics WG general meeting

  19. 2. ZhqqWW*qq+lvqq@ 250 GeV, L=250 fb-1, Mh=120 GeV • Find one-isolated lepton • Isolated track finding • lepton identification • Remove one-isolated lepton • Four-jets clustering to remaining sOne on-shell W (Wlv, Wqq)Mjj~MZ and M4j~MH • Minimum c2 combination (c2lv, c2qq) W1 Z H W2 lepton + 4 jet final state qH=qww=qcm-qz qmis=qcm-qall qWlv= qmis+ql ILC physics WG general meeting

  20. HWW*lvqq reconstruction Reconstruct as one-isolated lepton+4 jet Mass correlation of Zqq + WWlvqq, Mwlv, Mwqq (MWlv=M(qlep+qmis)) HWWqqqq HOthers HWWlvqq MWjj MWlv Require Wlv on-shell to suppress hothers and qqqq backgrounds ILC physics WG general meeting

  21. ZhqqWW*qq+vlqq@ 250 GeV, L=250 fb-1, Mh=120 GeV hWW*lvqqselection (RequireWlvis on-shell) 65<Mwlv<110 GeV, 10<Mwqq<50 GeV 10 < PT < 80 GeV |PZ|< 50 GeV NPFO > 60 (Remove leptonic channel) Thrust < 0.85 Thrust_minor > 0.1 -Log10Y34 < 2.5 χ2W<60 (Suppress WWvlqq BGs) 65 < Ewlv< 110 GeV (Suppresvlqq BGs) 80 < MZ < 100 GeV (Suppress WW BGs) Missing mass <50 GeV (vlqq and qq suppress) 105<Mh<140 GeV ILC physics WG general meeting

  22. Reconstructed Higgs mass distributionZhqqWW*qq+vlqq Ecm=250 GeV, L=250 fb-1, Mh=120 GeV eL(-0.8, +0.3) eR(+0.8, -0.3) Higgs mass (GeV) Higgs mass (GeV) Signal significance=9.4 ΔσBR/σBR=10.7% Signal significance=10.6 ΔσBR/σBR=9.6% ILC physics WG general meeting

  23. hWW* @250 GeV summary hWW* study @ 250 GeV, L=250 fb-1, Mh=120GeV ZhvvWW*vv+qqqq ZhqqWW*qq+vlqq ILC physics WG general meeting

  24. Higgs BRs summary table Current available results are summarized with all full simulation Zh or vvh (fusion) is different at the CM energy ILC physics WG general meeting

  25. Conclusion • Performance of “Possible BR decays” should be shown to demonstrate the potential of ILC measurement • DBD physics chapter and summary • vvh @ 1 TeV benchmark study is now on-going • Summarize to LC note • Several studies should be continue • Different Ecm, Mh=125 GeV • hZZ* (I studied but now pending…) should be done. ILC physics WG general meeting

  26. backup ILC physics WG general meeting

  27. ZhvvWW*vv+4j eL(-0.8,+0.3) @250 GeV L=250 fb-1 Signal significance=8.2 Remaining BGs are hothers and vlqq ILC physics WG general meeting

  28. ZhvvWW*vv+4j eR(+0.8,-0.3)@ 250 GeV L=250 fb-1 Signal significance=10.6 Remaining BGs are hothers and vlqq ILC physics WG general meeting

  29. ZhqqWW*qq+vlqqeL(-0.8,+0.3)@ 250 GeV, L=250 fb-1, Mh=120 GeV ILC physics WG general meeting Signal significance=9.5

  30. ZhqqWW*qq+vlqqeR(+0.8,-0.3)@ 250 GeV, L=250 fb-1, Mh=120 GeV Signal significance=10.4 ILC physics WG general meeting

  31. Lepton ID for Wlv with CAL information • HWW*mu vqq • HWW*e vqq • HWW*tau vqq • HWW*qqqq • H others MuID: Etotal/P < 0.6, Eecal/Etotal<0.5 eID: 0.6<Etotal/P<1.4, Eecal/Etotal>0.9 e mu mu e ILC physics WG general meeting

  32. One-isolated lepton for Wlv Find isolated lepton from charged tracks (EtrkvsEcone(5 degree)) HOthers HWWlvqq HWWqqqq E_tkr E_Cone EPFO>√(Econe+10) && EPFO<90-9/7.5*Econe E_trk E_cone Apply lepton ID with CAL information ILC physics WG general meeting

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