−Table of Contents
Monte Carlo Optical Data
Quantum Efficiency of PMT
The PMT used for data collection is a Hamamatsu R1332, with quantum efficiency spectrum given by the manufacturer. For Bialkali, we used the spectrum shown here:
| Figure 1: Quantum Efficiency of PMT |
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This spectrum can be compared to the one given by Hamamatsu for Bialkali.
If not otherwise stated, the properties of the PMT photocathode were inherited from G4Material::Bialkali. The reflectivity of the photocathode was taken to be R=0, ideal.
Plastic Scintillator Optical Characterization
The plastic scintillator was characterized by the following GEANT4 optical parameters for all energies:
| Table 1: Optical Properties of Scintillator | |
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| ABSLength | 2.5m (bulk attenuation at 423 nm) |
| RIndex | 1.58 (refractive index at 423 nm) |
| Scintillation Yield | 10000/MeV (according to EJ212) |
| ResolutionScale | 1.0 |
| FastTimeConstant | 2.4ns (decay time) |
Birk's Constant = 0.149 mm/MeV (L. Reichhart et al., Phys. Rev.)
As a note, there is no slow time constant being used (at least, not one that's assigned explicitly), and the values for reflectivity still need to be measured/assigned.
Relative light output:
New values (based on data taken by DMP, located on Dropbox here):
| Figure 2: Relative Light Output of Scintillator (Current/New) |
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Previously, the following spectrum had been used to characterize the relative light output of the scintillator:
| Figure 3: Relative Light Output of Scintillator (Old) |
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