Physics Performance Study

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Physics Performance Study by QuickSim
Tamaki Yoshioka (ICEPP)
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Introduction

• First step Establish analysis method by using
  ZH channel
• of the fast simulator (QuickSim).
• - Data equivalent to 70 fb-1 for both signal (ZH)
  and background
• (WW, ZZ, enW) have been produced.
• Higgs search was performed by selecting 2-jet
  and 4-jet
• in the final state using the data.
• Note that jet energy resolution for the QuickSim
  was tuned to
• be 30/vE.

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Event Display
ZH event
Ecm 350 GeV Mhiggs 120 GeV
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Higgs Selection 2-jet mode

• Signal Signature 2 jets large missing energy
• Mass of Observed particles Higgs
• Mass of Un-observed particles Z0
• Selection Criteria
• 1. Visible Energy 90 170 (GeV)
• 2. Missing Pt gt 20 (GeV)
• 3. Missing Mass lt 110 (GeV)
• 4. No. of Off Vertex Tracks gt 5

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Higgs Search _at_ 70 fb-1 (2-jet)
Signal All Background
All Background (WW, ZZ, enW)
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Higgs Selection 4-jet mode

• Signal Signature 4 jets
• Mass of 2-jet pair
• Mass of other 2-jet pair Z0
• Selection Criteria
• 1. Visible Energy gt 260 (GeV)
• 2. Thrust lt 0.90
• 3. Jet Pairing
• Select jet pairs, where both a mass of 2-jet
  pair
• and a missing mass of other 2-jet pair are
  consistent
• with Z0. Then form chi square.
• 4. No. of Off Vertex Tracks gt 5

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Higgs Search _at_ 70 fb-1 (4-jet)
Signal All Background
All Background (WW, ZZ, enW)
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Next Step

• Will produce more (500fb-1) data.
• Will analyze 2 lepton mode.
• Try another detector parameter sets.
• (Jet energy resolution 40/vE)
• Multi Higgs and SUSY channel.