The development of a plastic scintillator for radiotherapy dosimetry

A plastic scintillator detector was developed and tested in a 6MV photon beam. The detector comprised a BCF60 plastic scintillator, Polymetyl-Methacrylate Resin optical fibre and photodiode SFH250. The detector was used to measure an inplane profile for the photon beam at a depth of 1.5 cm for a field size of 10x10cm2 at 100 cm SSD. The photon beam was delivered by a Siemens linear accelerator. A comparison was made with the results obtained by cylindrical chambers CC04 and CC13, commercial diode PFD and a stereotactic diode SFD, all from the manufacturer IBA-Wellhöfer. An analysis was performed using the Gamma Evaluation method and the agreement was acceptable for a criterion of Distance To Agreement = 2 mm and Dose Difference = 2%.