Monte Carlo calculations of the absorbed dose and energy dependence of plastic scintillators.
Detector systems using plastic scintillators can provide instantaneous measurements with high spatial resolution in many applications including small field and high dose gradient field applications. Energy independence and water equivalence are important dosimetric properties that determine whether a detector will be useful in a clinical setting. Using Monte Carlo simulations, we calculated the energy dependence of plastic scintillators when exposed to photon beams in the radiotherapeutic range. These calculations were performed for a detector comprised of a BC-400 plastic scintillator surrounded by a polystyrene wall. Our results showed the plastic scintillation detector to be nearly energy independent over a range of energies from 0.5 to 20 MeV. The ratio of the dose absorbed by the scintillator to that absorbed by water was nearly a constant, approximately equal to 0.98 over the entire energy range of interest. These results confirm the water equivalence of the plastic scintillation detector and are in very good agreement with earlier results obtained using Burlin cavity theory.
Department of Radiation Physics, Division of Radiation Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030, USA. abeddar@mdanderson.org
A Sam
AS
Beddar
Tina Marie
TM
Briere
Firas A
FA
Mourtada
Oleg N
ON
Vassiliev
H Helen
HH
Liu
Radhe
R
Mohan
D003198:Computer Simulation; D017076:Computer-Aided Design; D004307:Dose-Response Relationship, Radiation; D004867:Equipment Design; D019544:Equipment Failure Analysis; D018499:Linear Energy Transfer; D008962:Models, Theoretical; D009010:Monte Carlo Method; D017785:Photons; D010969:Plastics / Q000737:chemistry* / Q000528:radiation effects*; D011829:Radiation Dosage; D011874:Radiometry / Q000295:instrumentation* / Q000379:methods; D012542:Scattering, Radiation
D010969:Plastics