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Update on H→WW→2 μ 2 ν Oct. 8, 2010

Update on H→WW→2 μ 2 ν Oct. 8, 2010. IFCA – U. Oviedo. Introduction. The work is going on in the HWW and WW analysis (focusing muons in the final state) We keep ourselves synchronized The list of Task proposed during last meeting is almost completely covered : Monte Carlo Trigger

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Update on H→WW→2 μ 2 ν Oct. 8, 2010

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  1. Update on H→WW→2μ2ν Oct. 8, 2010 IFCA – U. Oviedo

  2. Introduction • The work is going on in the HWW and WW analysis (focusing muons in the final state) • We keep ourselves synchronized • The list of Task proposedduring last meeting is almost completely covered: • Monte Carlo • Trigger • Tag and Probe • Fake Rates • Jet Veto • Top tagging • Drell-Yan estimation • Plus Multivariate Techniques (BDT) in WW and HWW Rebeca Gonzalez Suarez (08/10/2010)

  3. WW synchronization • The μμ channel was already synchronized: Rebeca Gonzalez Suarez (08/10/2010)

  4. WW synchronization • Also synchronized in ee and eμ: Rebeca Gonzalez Suarez (08/10/2010)

  5. Updated selection for WW • Some changes were proposed for the WW analysis: • Use of a tighter cut in the projected MET • Open the η of the jets from 3 to 5 • Muon PT range from 20/20 to 10/20 (2 regions) • The HWW analysis is planned to go as close as possible the the WW analysis : • We don’t use the projected MET (yet, will be studied) • The PT range in Higgs is already 10/20 • We can implement the change in the η of the jets considered for the CJV (that should be identical) Rebeca Gonzalez Suarez (08/10/2010)

  6. Effect of the proposed selection Monte-Carlo WW Spring10 sample Baseline WW analysis (WW sample, μμ channel) Gain of ~ 30% for signal Rebeca Gonzalez Suarez (08/10/2010)

  7. The new selection in perspective Normalizing to 1fb-1 @ 7TeV For WW signal and some of the main processes to be studied 30% better in signal, similar for top and effective against Zμμ With 100pb-1, it will mean the selection of more than one signal event (~6), with < 2 events of background Rebeca Gonzalez Suarez (08/10/2010)

  8. Status of the HWW analysis Following WW direction: Muon selection becomes identical (10/20) Same MET (Track corrected) Same Jets for the Central Jet Veto (PF, |η| < 5, ETRAW > 20) Test of the cut evolution 3.1pb-1 QCD, W+jets, Z+jets, top, WW, WZ, ZZ, tW included Cross-sections × BR (leptons) for Higgs signal < 1 pb (NNLO) selection efficiencies of the analysis at muon selection level are < 10% (for μμ) : with 10 pb-1 at muon selection < 0.9 Higgs events (160) expected in this channel Rebeca Gonzalez Suarez (08/10/2010)

  9. Kinematical distributions Everything in good shape Still far from the start of the real the work here 3.1 pb-1 After CJV Rebeca Gonzalez Suarez (08/10/2010)

  10. Trigger Studies Electron and muon triggers systematically checked for each table once samples are available Check results can be found in the twiki https://twiki.cern.ch/twiki/bin/viewauth/CMS/HiggsWGHLTValidate And in the offline DQM GUI DQMGUI Example Next: 1032 Waiting for Higgs to WW samples Some examples for 2E31 trigger Menu, performed with 3.9.0.pre5 RelVal samples in next slide (with tt Fastsim, no HWW available) lowest unprescaled: HLT_Mu11 HLT_Ele17_SW_CaloEleId_L1R  high eff. for dilepton final states Would like to study new triggers in 1E32 table  samples? Rebeca Gonzalez Suarez (08/10/2010)

  11. Trigger Efficiencies Efficiency Vs η and PT HLT_Mu11 HLT_Ele17_SW_CaloEleId Efficiency definition: fraction of selected events passing HLT requirement (top selection eμ) Rebeca Gonzalez Suarez (08/10/2010)

  12. Tag and Probe Zmm VBTF cuts • Tag: • GlobalMuonPT • TrackerMuon • HLT_Mu9 • |η| < 2.1 • pT > 20 GeV • |d0 | < 0.2 • Isolated • GM normalized χ2 < 10 • At least one pixel hit • Segments matched in at least 2 muon stations • At least one muon hit matched to the global fit • Number of tracker hits > 10 • Probes: • Trackswith pT > 5 GeV Passing probes: • GlobalMuonPT • TrackerMuon • |h| < 2.4 • pT > 20 GeV • |d0 | < 0.02 • Isolated • At least one muon hit matched to the global fit • Number of tracker hits > 10 Monte Carlo: Zmumu Summer10 sample With all certified data up to now: 4.43 pb-1 (/Zmumu/Summer10-START36_V9_S09-v1/GEN-SIM-RECO) Rebeca Gonzalez Suarez (08/10/2010) 12

  13. Muon ID + Iso Efficiency of the Muon ID + isolation cuts, obtained in data Vs Monte-Carlo, as a function of the PT of the ‘Probe’ And as a function of the η of the ‘Probe’ Rebeca Gonzalez Suarez (08/10/2010)

  14. Trigger Efficiency using T&P Trigger efficiency defined as the fraction of muon fulfiling all the muonID + Isolation criteria and matching a HLT_Mu9 object Data: MC: Rebeca Gonzalez Suarez (08/10/2010)

  15. Fake Rates • The work started with the very early data • Last time we presented this: • It was a single muon rate measured in data with less than 15 nb-1 using tracks • The data available and the Monte Carlo were in agreement Higgs contribution to MUO-10-002 Rebeca Gonzalez Suarez (08/10/2010)

  16. l+d method • For WW and Higgs to WW, we have a method extensively studied in the CSA07 context oriented to the estimation of the W+jets background in di-muon final states • Well known and documented: CMS AN 2008/039 • Several talks about it available, for example (8 June): • http://indico.cern.ch/contributionDisplay.py?contribId=2&confId=88524 • Basically the idea is to look at QCD events with one good muon and look at the ‘fakeable objects’ that can be mistaken as a second muon (background in the analysis) • It is already possible to start the study in data Rebeca Gonzalez Suarez (08/10/2010)

  17. First Results with 4.43 pb-1 • Cleaning the data sample from W, Z and top events (loose VBTF and top selections) • Using the JetMet, JetMETTau and Jet datasets • Comparing with QCD inclusive Mu 15 Still lacking statistics in some PT bins to fully perform it The QCD selection in data can also be done in a better way (on going) Rebeca Gonzalez Suarez (08/10/2010)

  18. Next Step in Fakes • But that’s not all: Parallel fake rate study done within the group for top (see http://indico.cern.ch/conferenceDisplay.py?confId=96963) • Slightly different approach • We are working in merge the two concepts in one that can be applied in all the analysis, HWW, WW and top Yesterday’s talk in top dilepton meeting by Alicia http://indico.cern.ch/getFile.py/access?contribId=2&resId=0&materialId=slides&confId=96963 Rebeca Gonzalez Suarez (08/10/2010)

  19. Jet Veto/Track Jets/b-tagging • Studies continuously going on by Lara (many presentations) • For 1fb-1 and the three final states together (μμ, eμ and ee) • Applying the WW baseline selection (including softmuon) • Two b-tagging algorithms tested: • Track Counting (TC) • Secondary Vertex efficiency (SV) • Summer 10 samples /VVJets_7TeV-madgraph/Summer10-START36_V10-v1/GEN-SIM-RECO /TTbar/Summer10-START36_V9_S09-v1/GEN-SIM-RECO Little effect on the signal while greatly reducing the ttbar background Evenifbothalgorithms are HighEff… TrackCounting More efficient/less purity Secondary Vertex  More purity/less efficiency Rebeca Gonzalez Suarez (08/10/2010)

  20. Tagging efficiencies As a function of thebtaggingdiscriminant TrackcountingHighEfficiencyalgorithm High Eff Simple Secondary Vertex Btaggingefficiency Btaggingefficiency Mistagrate Mistagrate Based on the requirement of a minimum number of good quality tracks with an impact parameter significance exceeding a given threshold. Reconstructs the B decay vertex using an adaptive vertex finder, and then uses variables related to it, to calculate its btaggingdiscriminant. Rebeca Gonzalez Suarez (08/10/2010)

  21. Taggingefficiencies As a function of the jet ET TrackcountingHighEfficiencyalgorithm HighEff Simple SecondaryVertexalgorithm All jets (PF Jets) are inside |h| < 2.5 Rebeca Gonzalez Suarez (08/10/2010)

  22. b-tagging Results without b-tagging (including softmuon cut) assuming 1 fb-1 VV  229.2 TTbar  23.0 Applying b-tagging Cutonthe ET of the jets used as input forthebtagging (after CJV) /VVJets_7TeV-madgraph/Summer10-START36_V10-v1/GEN-SIM-RECO /TTbar/Summer10-START36_V9_S09-v1/GEN-SIM-RECO Rebeca Gonzalez Suarez (08/10/2010)

  23. HWW Multivariate Analysis (BDT) • We keep as up to date as possible the multivariate analysis for HWW and WW • We are starting to check the behavior of the data using our latest Training • Still need more statistics to fully prepare a dedicated training for 7 TeV -> Very early preliminary studies with data tt WW Z Example of the Higgs trainings at 7 TeV against WW, tt and Z+jets with data with 3.1pb-1 (not yet optimized) Rebeca Gonzalez Suarez (08/10/2010)

  24. Summary • Work ongoing in most of the main tasks of the WW and HWW analysis: • Synchronized and in-tune with the HWW and WW working groups • Trigger Validation done in every new release • Effort focused in Tag and Probe, Fake rates and top background estimation (CJV, Track jets and b-tagging) • Cut-based Analysis for WW and HWW is ready for the data • Continuous work in the Multivariate Analysis (BDT) • Also a Particle Flow study based in Particle Flow Muons, Met and Jet is going on (coming soon) Rebeca Gonzalez Suarez (08/10/2010)

  25. Backup

  26. b-tagging (TCHighEfficiency) PF Jets trackJets caloJets JPT Rebeca Gonzalez Suarez (08/10/2010)

  27. b-tagging (HighEffSimpleSecondaryVertex) trackJets PF Jets JPT caloJets Rebeca Gonzalez Suarez (08/10/2010)

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