Update on WH to 3 lepton AnalysisAnd

Electron Trigger Efficiencies with Tag And Probe

Nishu1, Suman B. Beri1, Guillelmo Gomez Ceballos2

1 Panjab University, Chandigarh2 Massachusuttes Institute of Technology , Cambridge

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Outline of Talk Update on WH to 3 leptons: Signal and Background Processes Selection Criteria Number of events expected at 1 fb-1

Summary

Electron Trigger Efficiencies:Introduction to Tag And Probe Analysis Strategy Data/Monte Carlo Comparison Plots HLT Efficiencies Summary

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SIGNAL & BACKGROUND PROCESSES

SIGNAL PROCESS

CROSS SECTION

(pb)

WH (130) 0.25

WH (140) 0.32

WH (150) 0.36

WH (160) 0.37

WH (170) 0.32

WH (180) 0.25

WH (190) 0.17

WH (200) 0.13

BACKGROUND PROCESS

CROSS SECTION

(pb)

WZ 18.2

ZZ 5.9

WW (2l) 4.5

Ttbar 157.5

tW 10.6

Zee 1666

Z 1666

Z 1666

Fall 10 MC Samples at a center of mass energy of 7 TeV are used. Full Simulation of the CMS detector response

using standard CMS Software is used.

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SELECTION CRITERIAHigh Level Triggers Used: Single muon/electron triggers:HLT_Mu9 OR HLT_Ele10_LW_L1R

Muon Selection : IsGlobalMuon & IsTrackerMuon Prompt Tight & N_Tracker_Hits >10 |d0 (PV)| < 0.025 cm Isolation condition : (Iso_{TRK} + Iso_{ECAL} + Iso_{HCAL}) / pt < 0.15,

deltaR cone = 0.3

Electron Selection: VBTF80 |d0 (PV)| < 0.025 cm Conversion rejection by looking for a track partner with |dist| < 0.02 and angle |dContagentTheta|<0.02 Isolation Condition: (Iso_{TRK} + MAX(0,Iso_{ECAL}-1) + Iso_{HCAL}) / pt < 0.1, deltaR cone = 0.3 4

Jet Reconstruction: PF jets Anti – Kt algorithm with cone size 0.5 || < 2.5 Leptons removed from Jets by requiring ∆R(lepton-jet) >0.4

MET Reconstruction: Use of Standard PFMet collection

Preselection Conditions : Exact 3 good leptons are required in an event with || < 2.5 and PT > 20/20/10 Total charge of these leptons is required to be either +1 or -1

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∆R BETWEEN TWO LEPTONS, DILEPTON MASS, LEADING JET PT &

MISSING TRANSVERSE ENERGY (MET)

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As the leptons coming from Higgs are aligned, so the angle between them (∆R) should be small. ∆R between 2 closest oppositely charged leptons < 1.0

As there is no Z involved in case of Signal Sample. |Dilepton mass - Zmass| > 20

Almost no or very low PT jets associated with signal. Leading Jet PT < 30 GeV

Large Missing Transverse Energy (MET) in the final state. MET > 40 GeV for and e. MET > 45 GeV for ee and MET > 50GeV for eee.

FINAL REQUIREMENTS

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NUMBER OF EVENTS EXPECTED AT 1fb-1

WZ ZZ WW Top and Single Top

DY

e 0.03 0.02

0.008 0.006

0.00.0 0.0 0.0 0.0 0.0

ee 0.05 0.03

0.008 0.006

0.0 0 0.0

0.016 0.016 0.0 0.0

0.03 0.01

0.01 0.0070.0

0.00.0 0.0 0.0 0.0

eee0.03 0.01

0.005 0.004

0.0 0.0 0.0 0.0 0.0 0.0

All 0.14 0.04

0.03 0.01 0.0 0.0 0.016 0.016 0.0 0.0

WH (130) WH (150) WH (160) WH (200) Total Backgroun

d

e 0.05 0.01 0.12 0.04 0.12 0.04 0.02 0.01 0.038 0.02

ee 0.04 0.01 0.06 0.02 0.09 0.03 0.03 0.01 0.074 0.03

0.016 0.01

0.03 2 0.015

0.05 0.02 0.006 0.003

0.04 0.01

eee 0.009 0.005

0.016 0.009

0.02 0.01 0.006 0.003

0.035 0.01

All 0.12 0.02 0.23 0.05 0.28 0.05 0.06 0.01 0.187 0.04

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SUMMARY

Simulation study on the channel WH WWW* l l l using standard CMS Software (CMSSW_3_8_6) and Fall 10 Monte Carlo data samples of 7 TeV is done at an integrated Luminosity of 1fb-1 .

Four different final states – eee, , ee and e of this channel with a Higgs mass range of 130 – 200 GeV/c2 are studied.

Number of events expected at 1 fb-1 are calculated.

Analysis helps adding toHiggs Sensitivity.

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ELECTRON TRIGGER EFFICIENCY STUDY FOR WW AND HWW USING OFFICIAL TAG AND PROBE PACKAGE

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Tag And Probe

• The tag-and-probe method is a powerful tool to measure reconstruction efficiency from data.• Utilize data from a clean dilepton sample, e.g., Z→ee/ • A "tag" is an electron/muon that passes a set of very tight selection criteria (isolation , Id conditions etc).• The existence of a tag lepton indicates the existence of the other leg from the same Z. • A "probe" is the other electron/muon coming from the Z, and it is selected by pairing with tag such that the invariant mass of the combination is consistent with the mass of Z. • The method begins to count when both "tag" and "probe" exist.

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ANALYSIS STRATEGY

CMSSW 3_8_5_patch3

Triggers Studied:HLT_Ele10_LW_L1R for runs [136033,139980]HLT_Ele15_SW_L1R  for runs [140058,141882]HLT_Ele15_SW_CaloEleId_L1R for runs [141956,144114]HLT_Ele17_SW_CaloEleId_L1R for runs [146428,147116] HLT_Ele17_SW_TightEleId_L1R for runs [147196,148058]HLT_Ele17_SW_TighterEleIdIsol_L1R_v2  runs [148819,149064]HLT_Ele17_SW_TighterEleIdIsol_L1R_v3 for runs [149181,149442]

https://twiki.cern.ch/twiki/bin/viewauth/CMS/WWFirstPaper#Triggers

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SAMPLES USED

Data and MC Samples

/EG/Run2010A-Sep17ReReco_v2/RECO /Electron/Run2010B-PromptReco-v2/RECO /DYToEE_M-20_TuneD6T_7TeV-pythia6/Fall10-START38_V9_preproduction-v1/GEN-SIM-RECODEBUG/DYToEE_M-20_CT10_TuneZ2_7TeV-powheg-pythia/Fall10-START38_V12-v1/GEN-SIM-RECO

JSON Used: Cert_132440-149442_7TeV_StreamExpress_Collisions10_JSON.txt

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SELECTION CRITIRIAGsfElectrons SC_Et>20GeV, ||<2.5 (exclude EB-EE gap region i.e. 1.4442 to 1.56 )

Isolation Condition:Barrel: dr03TkSumPt + max(0., dr03EcalRecHitSumEt - 1.) + dr03HcalTowerSumEt) / Pt < 0.1

Endcap: dr03TkSumPt + dr03EcalRecHitSumEt + dr03HcalTowerSumEt) / Pt< 0.1

Electron Id Cuts: gsfTrack.trackerExpectedHitsInner.numberOfHits <= 0

Barrel:(sigmaIetaIeta<0.01) && ( -0.06<deltaPhi<0.06 ) && ( -0.004<deltaEta<0.004 ) && (hadronicOverEm<0.04)

Endcap:(sigmaIetaIeta<0.03) && ( -0.03<deltaPhi<0.03 ) && ( -0.007<deltaEta<0.007 ) && (hadronicOverEm<0.025) 14

Efficiencies of HLT_Ele10_LW_L1R & HLT_Ele15_SW_L1R

HLT_Elec10_LW_L1RHLT_Elec10_LW_L1R

HLT_Ele15_SW_L1R HLT_Ele15_SW_L1R

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Efficiencies for HLT_Ele15_SW_CaloEleId_L1R &

HLT_Ele17_SW_CaloEleId_L1R

HLT_Ele15_SW_CaloEleId_L1R HLT_Ele15_SW_CaloEleId_L1R

HLT_Ele17_SW_CaloEleId_L1R HLT_Ele17_SW_CaloEleId_L1R

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Efficiency for HLT_Ele17_SW_TightEleId_L1R

HLT_Ele17_SW_TightEleId_L1R

HLT_Ele17_SW_TightEleId_L1R

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HLT_Ele17_SW_TighterEleIdIsol_L1R_v2 &

HLT_Ele17_SW_TighterEleIdIsol_L1R_v3

HLT_Ele17_SW_TighterEleIdIsol_L1R_v2 HLT_Ele17_SW_TighterEleIdIsol_L1R_v2

HLT_Ele17_SW_TighterEleIdIsol_L1R_v3 HLT_Ele17_SW_TighterEleIdIsol_L1R_v3

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AVERAGE EFFICIENCY OF COMBINATION OF TRIGGERS OVER

WHOLE RUN RANGE

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TRIGGER EFFICIENCY VALUESTrigger Barrel Endcap

Average efficiency of Combination of Triggers over whole run range

0.9772 0.0015 0.9628 0.003

HLT_Ele10_LW_L1R runs [136033,139980]

1 0.029 10.071

HLT_Ele15_SW_L1R  runs [140058,141882]

1 0.014 10.038

HLT_Ele15_SW_CaloEleId_L1R runs [141956,144114]

0.989 0.003 0.9780.0013

HLT_Ele17_SW_CaloEleId_L1R runs [146428,147116]

0.993 0.0023 0.9860.004

HLT_Ele17_SW_TightEleId_L1R runs [147196,148058]

0.977 0.0029 0.967 0.0054

HLT_Ele17_SW_TighterEleIdIsol_L1R_v2  runs [148819,149064]

0.973 0.003 0.953 0.006

HLT_Ele17_SW_TighterEleIdIsol_L1R_v3  runs [149181,149442]

0.967 0.0038 0.948 0.00720

SUMMARY Trigger efficiencies for electrons passing identification and isolation in a Z control sample by matching the probe lepton to the relevant HLT trigger object candidate were computed.

The average Trigger efficiency of the various Electron triggers used over the relevant run ranges was found.

As there are two leptons in the final state, the probability of both leptons failing the lepton trigger is very small. The efficiency for the event to pass the Trigger = (1-(1- Trigger Eff)2). It comes out to be 99.9 % in case of ee.

This study is included in CMS Analysis Notes – CMS AN -2010/411 “Search for Higgs Boson Decays to two W Bosons in the Fully Leptonic Final State at √s = 7 TeV” and CMS AN-2010/344, “First Measurement of pp → WW Production Cross-Section at √s = 7 TeV”.

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FUTURE PLANS

To continue with the study on associated Higgs (WH) production channel with H WW* in the 3 leptons final state using the latest versions of CMSSW .

To work on the Systematics related to this study.

To continue the work on WW with the real data in 2011. To Study the efficiencies of the various Electron Triggers (Single/Double Lepton Triggers) that are planned to be used during this year.

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