Plastic Scintillator Calculation
Below is the calculations done to determine the probability of pair production depending on thickness of the scintillator.
Molecules per volume [math]\displaystyle{ = \frac{grams CH_{2}}{cm^3} * \frac{mol}{gram} * \frac{N[A]}{mol} }[/math]
Weighted cross-section [math]\displaystyle{ = (\sigma_{elec}C + \sigma_{nucleus}C) + 2(\sigma_{elec}H + \sigma_{nucleus}H) }[/math]