Doped plastic scintillator properties for soft tissue dosimetry

• Main Authors: Tajudin, S. M., Namito, Y., Sanami, T., Hirayama, H., Hashim, S.
• Format: Article
• Published: Institute of Electrical and Electronics Engineers Inc. 2022
• Subjects: QC Physics
• Online Access: http://eprints.utm.my/104445/; http://dx.doi.org/10.1109/TNS.2022.3196353

In medical dosimetry, the radiation quantity of interest is frequently the dose to tissue. To make direct dosimeters that show the dose absorbed in soft tissue, tissue-equivalent material is preferred. Plastic scintillators (PLS) are made of materials with a density similar to soft tissue and relatively have energy independent response. Non-proportionality must be taken into account when reproducing the light output spectrum for photons below 200 keV, as it reduces light output significantly. In comparison to a standard plastic scintillator, both low and high energy photons’ pulse height distribution spectra as a result of lead doping were measured and calculated. The effect of a 0.5 % lead doping scintillator is sufficient to make up for the loss or difference between soft tissues and plastic scintillators in response to low energy photons, particularly below 200 keV.