TP Calorimetry and particle ID

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TP Calorimetry and particle ID

• Jaewon Park

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Calorimetry

• We assumed that (dE/dx)min is constant for
  different particles.
• In previous study
• Hcal calibration constant is acquired from proton
  beam study.
• Ecal calibration constant is acquired from
  electron beam study.
• In TP(trackerDS-Ecal) study, it shows we cant
  use same calibration constant for proton and
  electron.

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Proton -- Ecal calibration constant

• Old study showed Ecal calibration constant 2.5 is
  better than 1.75
• Mean of (recoE-trueE)/trueE become constant for
  theta, Vz depedence
• Value 1.75 is from dE/dx weighting.
• Calorimetry constant 2.5 overestimates protons
  energy.

K_ecal2.5
K_ecal1.5
K_ecal1.75
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TP Detector Proton

• Ecal calib. constatant 2.5

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Nu_e electron events (k_ecal1.5)

• It underestimates electrons energy.

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Nu_e electron energy (k_ecal2.5)

• 2.5 shows better energy reconstuction.
• Its consistent with previous Ecal study with
  electron beam.

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Nu_e electron energy (k_ecal2.5)

• When electron track is reconstructed.

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dE/dx

• From graph, dE/dx (electron) is higher thatn
  dE/dx (proton) around 2-5GeV

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dE/dx of reconstructed tracks

• Particle beam is shot perpendicular to
  scintillator planes in semi-infinite tracker.
• To localize only beginning of track, it process
  dE variable until
• slopegt1, drgt1, and nStripsgt3
• Also required track length gt 10cm.
• Examined two variables
• dE variable in track ntuple.
• Sum of dE / track length

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dE/dx of reconstructed tracks
Mean value
Mean value

• Upper two plots shows mean values of distribution
• Bottom two plots shows Gaussian fit values of
  distribution.

Fit value
Fit value
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dE sum / track length

• dE sum/ trk length gt 0.18
• Low energy proton dE/dx looks like electron or
  gamma.

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dE sum / track length
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(Backup slides)

• dE sum/track length individual plots

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Gamma
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Gamma
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Electron
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Electron
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Proton