Proton induced radiation damage studies on plastic scintillators for the Tile calorimeter of the atlas detector

4.2.1.
 
Light Transmission spectroscopy 
Transmission spectroscopy was conducted using the Varian Carry 500 
spectrophotometer. A photograph of the spectrophotometer is shown below. The 
spectrophotometer uses a lamp source and diffraction grating in order to produce 
a differential wavelength spectrum of light. A tungsten lamp source produces 
light over the visible spectrum, whilst a deuterium lamp source produces light 
across the ultra violet spectrum.
Light transmission measurements were conducted over the wavelength range of 
300-800 nm. The spectrophotometer allows for a dual beam so that transmission 

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may be measured relative to a control sample. The transmission of each sample 
was measured relative to air.
Figure 4-10: Photograph of the Varian Cary 500 spectrophotometer.
Samples were tested prior to irradiation as well as on the day of irradiation, 1 
day, 2 days, 1 week and 4 weeks after irradiation. Testing was done over several 
days after irradiation in order to observe healing of the transpare ncy loss in the 
scintillators. Measurements were also made for a control sample for each grade 
on each respective day in order to correct for any day to day systematic 
fluctuations.
A baseline as well as zeroing calibration were performed on the machine p rior to 
each days testing. Measurements were taken for four different mounting positions 
of the sample within the machine (2 per cross-sectional face) and the average 
spectra was processed for analysis thereafter. Samples were mounted behind a 
slide containing a 1 mm diameter hole through which light was incident, thereby 
ensuring that only the irradiated regio ns of each sample was measured. 
4.2.2.
 
Light yield testing in response to