Quartz Plate Calorimeter Prototype Geant4 Simulation Progress

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Quartz Plate Calorimeter Prototype Geant4
Simulation Progress

• W. Clarida
• The University of Iowa

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Outline

• Introduction
• First simulation model, and results
• Realistic simulation model, and results
• Future work

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Introduction

• While working on the HE Upgrade (Quartz Plate)
  RD we started to plan a Quartz Plate
  Calorimeter Prototype.
• First studies were Geant4 simulations of an
  approximate model calorimeter.
• As the RD results shaped the ideas we started to
  design and simulate the prototype.
• QPCAL has partially tested at Feb 06 Fermilab
  test beam, then full calorimeter (20 layers)
  tested for 66GeV and 120GeV protons on Sept 06
  test beam.
• In Nov we have CERN test beam that will cover
  pion and electron beams
• All these tests have to be simulated as well. As
  realistic as possible. This is ongoing project.

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1st Gen. Model Quartz Plate Prototype

• A matrix of 3x3 towers with alternating 4.5 mm
  Cu and 0.5 mm Quartz plates is constructed.
• (30cm x 30cm x 100 cm)
• To study detector geometry optimization.
• Geant4 read-out studies.

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Shower Development 1
Electromagnetic and hadronic shower developments
were simulated with electron and pion beams at
different energies.
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Energy Resolution Linearity
The energy resolution and linearity were
calculated for different beam energies.

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The Prototype Design

• RD results and initial model shaped the
  prototype.
• The final design
• 20cm x 20cm, 20 layers 70 mm iron, 5 mm quartz

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The Fiber Geometry

• We used the bar geometry on the prototype.
• The fibers in the actual prototype are 1mm
  diameter Bicron wavelength shifting fibers. They
  absorb photons down to 280 nm, emit 435 nm.
• Currently however the simulation uses HE fibers.
  
• The fibers go 20 cm out of the quartz.

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Shower Development 2

• Simulations of shower development in our present
  prototype.
• This will be compared to the Pion and Electron
  test beam at CERN
• Pion test beam will be with 7cm absorber.
• Electron will be with 2cm absorber. (currently
  being simulated)

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Shower Development

• Simulations of proton shower development in our
  present prototype.
• 5cm absorber as this is what is supplied at
  Fermilab.
• Must still increase statistics.

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Geant4 Simulations of Prototype
These simulations still need to be improved. We
need more energies of the different particles as
well as more statistics of the present energies.
Also the current fibers are not the fibers that
will be used in the final design.
Geant4 simulation of 2 GeV electron with our
current configuration of 70mm iron absorber, 5 mm
quartz plate prototype calorimeter.
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Energy Resolution Hadrons
The energy resolution of the different simulated
beam energies.
Preliminary
Typical simulated signal distribution
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Energy Resolution Electrons
The energy resolution is simulated with different
beam energies. Only 7cm simulations.
Preliminary
Typical simulated signal distribution
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Detector Linearity
The detectors linearity is from the same beam
energies. Again 7cm absorber thickness for Pions
and 5cm for Protons. This graph also suffers
from a lack energy range in the simulations.
Preliminary
Preliminary
Electron Linearity for 7cm Absorber depth.
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Plans

• Use our CPU time
• Increase statistics of current energies.
• Fill in gaps and extend the range to complete
  energy resolution.
• Complete electron simulations for thinner
  absorber.
• Compare signal creation in the quartz to signal
  received by the PMTs.
• Look at the transverse shower profiles to make
  sure that all of the Cerenkov signal is being
  contained.
• Tweak our simulation
• Improve the description of the fibers to reflect
  the entire absorption range.
• Make Tyvek reflectivity more realistic with
  wavelength dependant reflectivity
• Create a simulation with scintillator to compare
  to test beam and quartz simulations
• Use different physics packages.