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High energy photon pairs from RS-1 Gravitons:
L1/HLT Studies
Vladimir Litvin, Toyoko OrimotoCaltech, CMS
WG4 Group Meeting01 June 2007
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Introduction
• Study to investigate L1 and HLT (in)efficiencies and optimize selection for an express stream for very high energy diphoton events
• MC Samples: • Produced at Caltech & Fermilab • CMSSW_1_3_1_hlt2 with additional CVS tags:
• V00-00-53 HLTrigger/btau• V00-00-26 HLTrigger/xchannel• V01-06-06 RecoLocalTracker/SiPixelClusterizer• V01-00-06 L1Trigger/L1ExtraFromDigis• V02-00-06 L1Trigger/L1ExtraFromMCTruthProd• V00-00-67 HLTrigger/Configuration
• CMSSW_1_3_1_hlt3• No Pileup
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MC Samples
• Signal RS-1 G: • ~90k events (131_hlt2) and ~80k (131_hlt3) each for 750,
1250, 1000, & 1500 GeV mass samples (with c = 0.1)• Background:
• Born: ~100k (131_hlt2) and ~100k (131_hlt3) events• Box: ~300k (131_hlt2) and ~100k (131_hlt3) events• CKIN(1) = 200 GeV
• low limit of the invariant mass of the two outgoing photons, with high end is set to infinity
• Done intentionally to reduce the number of events to produced while keeping the most useful part of the backgrounds for our studies.
born box
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Invariant Masses
1443.0 ± 0.326.6 ± 0.3
720.5 ± 0.115.0 ± 0.2
960.5 ± 0.219.9 ± 0.2
Still need energy correction
Candidates reconstructed from two Island Basic Clusters from ECAL Barrel/Endcap with pt>(30) 100 GeV
born box
750 1000 1500
Pt_photons > 30Pt_photons > 100
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L1 Trigger Efficiencies (131_hlt2)# non-zero L1 bits
per event L1 bits set to 1
750 GeV
born
box
1000 GeV
1500 GeV
# non-zero L1 bits per event L1 bits set to 1
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L1 Trigger Efficiencies (131_hlt3)# non-zero L1 bits
per event L1 bits set to 1
750 GeV
born
box
1000 GeV
1500 GeV
# non-zero L1 bits per event L1 bits set to 1
1250 GeV
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L1 Egamma Efficiencies (131_hlt2)
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L1 Egamma Efficiencies (131_hlt2)
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L1 Egamma Efficiencies (131_hlt3)
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L1 Egamma Efficiencies (131_hlt3)
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HLT Efficiencies (131_hlt2)# non-zero HLT bits
per event HLT bits set to 1
750 GeV
born
box
1000 GeV
1500 GeV
# non-zero HLT bits per event HLT bits set to 1
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HLT Efficiencies (131_hlt3)# non-zero HLT bits
per event HLT bits set to 1
750 GeV
born
box
1000 GeV
1500 GeV
# non-zero HLT bits per event HLT bits set to 1
1250GeV
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HLT Egamma Efficiencies
• 131_hlt2:
• 131_hlt3:
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HLT Egamma Efficiencies
• Decrease in EG HLT efficiencies with increasing mass resonance is due to tight cut on energy deposition in HCAL for EG objects…
• If E > 6 GeV in HCAL for cluster from ECAL Barrel (8 GeV for ECAL Endcap), then the HLT object is considered *not* an EG object..
• Currently this cut is too tight for our very high energy diphotons
• Use HoE cut instead…Will be implemented shortly in CMSSW_1_3_1_hlt4
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Selection
• Invariant mass, pt cuts• Shape (S1/S9, S9/S25)• ECAL Isolation• HCAL energy deposition• Track Isolation• Jets
• Plots will be shown for only 750 GeV sample & born and box backgrounds
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ECAL S1/S9 (131_hlt2)
Note: this is only for Barrel
Higher energy photon Lower energy photon
Pt_photons > 30Pt_photons > 100
750 GeV
born
box
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ECAL S1/S9 (131_hlt3)
Note: this is only for Barrel
Higher energy photon Lower energy photon
Pt_photons > 30Pt_photons > 100
750 GeV
born
box
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ECAL S9/S25 (131_hlt2)
Note: this is only for Barrel
Higher energy photon Lower energy photon
Pt_photons > 30Pt_photons > 100 750
GeV
born
box
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ECAL S9/S25 (131_hlt3)
Note: this is only for Barrel
Higher energy photon Lower energy photon
Pt_photons > 30Pt_photons > 100 750
GeV
born
box
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ECAL Isolation (131_hlt2)
Higher energy photon Lower energy photon
Energy from basic clusters summed within R cone of 0.3 around basic cluster of photon candidates
Pt_photons > 30Pt_photons > 100 750
GeV
born
box
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ECAL Isolation (131_hlt3)
Higher energy photon Lower energy photon
Energy from basic clusters summed within R cone of 0.3 around basic cluster of photon candidates
Pt_photons > 30Pt_photons > 100 750
GeV
born
box
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HCAL Energy Deposit: HBHE (131_hlt2)
Energy from HCAL Rechits summed within R cone of 0.3 around basic cluster of photon candidate
Higher energy photon Lower energy photon
Pt_photons > 30Pt_photons > 100
750 GeV
born
box
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HCAL Energy Deposit: HBHE (131_hlt3)
Energy from HCAL Rechits summed within R cone of 0.3 around basic cluster of photon candidate
Higher energy photon Lower energy photon
Pt_photons > 30Pt_photons > 100
750 GeV
born
box
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HCAL Energy Deposit: HO (131_hlt2)
Energy from HCAL Rechits summed within R cone of 0.3 around basic cluster of photon candidate
Higher energy photon Lower energy photon
Pt_photons > 30Pt_photons > 100
750 GeV
born
box
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HCAL Energy Deposit: HO (131_hlt3)
Energy from HCAL Rechits summed within R cone of 0.3 around basic cluster of photon candidate
Higher energy photon Lower energy photon
Pt_photons > 30Pt_photons > 100
750 GeV
born
box
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Tracker Isolation (131_hlt2)
Higher energy photon Lower energy photon
Pt_photons > 30Pt_photons > 100
750 GeV
born
box
Number of tracks (with pt >10) within R cone = 0.3 around basic cluster of photon candidate Check also pt=[3,5] and R=[0.4,0.5]
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Tracker Isolation (131_hlt3)
Higher energy photon Lower energy photon
Pt_photons > 30Pt_photons > 100
750 GeV
born
box
Number of tracks (with pt >10) within R cone = 0.3 around basic cluster of photon candidate Check also pt=[3,5] and R=[0.4,0.5]
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Jets (131_hlt2 + pt>30 GeV)
PtnJets eta phi
750 GeV
born
box
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Jets (131_hlt3 + pt>30 GeV)
PtnJets eta phi
750 GeV
born
box
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Next Steps
• Production:• CMSSW_1_3_1_hlt4• Produce gamma+jet and QCD backgrounds with
generator preselection (working on filter now)• CompHep events for 2gamma+2jets and
gamma+3jets (not the top priority now) • Analysis:
• HoE selection• Energy correction
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Backup Slides
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All L1 Efficiencies (131_hlt2)
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All L1 Efficiencies (131_hlt2)
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All L1 Efficiencies (131_hlt2)
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All L1 Efficiencies (131_hlt2)
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All L1 Efficiencies (131_hlt2)
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All L1 Efficiencies (131_hlt3)
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All L1 Efficiencies (131_hlt3)
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All L1 Efficiencies (131_hlt3)
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All L1 Efficiencies (131_hlt3)
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All L1 Efficiencies (131_hlt3)
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All HLT Efficiencies (131_hlt2)
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All HLT Efficiencies (131_hlt2)
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All HLT Efficiencies (131_hlt2)
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All HLT Efficiencies (131_hlt3)
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All HLT Efficiencies (131_hlt3)
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All HLT Efficiencies (131_hlt3)
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Jets (131_hlt2 + pt>50 GeV)
PtnJets eta phi
750 GeV
born
box
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Jets (131_hlt2 + pt>70 GeV)
PtnJets eta phi
750 GeV
born
box
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Jets (131_hlt3 + pt>50 GeV)
PtnJets eta phi
750 GeV
born
box
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Jets (131_hlt3 + pt>70 GeV)
PtnJets eta phi
750 GeV
born
box