Verification of percentage depth dose of MAGICA polymer gel dosimeter with electron beams

Abstract

In this work investigation of the normoxic MAGICA polymer gel dosimeter has been undertaken. Using MRI, the formulation to give the maximum change in the transverse relaxation rate R2 was determined to be 8% gelatin, 0.5% agarose, 9% methacrylic acid, 0.0352% ascorbic acid, 0.0015% CuSO4.5H2O, 0.002% hydroquinone and 82.3% HPLC(Water).When the preparation of final polymer gel solution is completed, it is transferred into phantoms and allowed to set by storage in a refrigerator at about 4C°. The optimal post-manufacture irradiation and post imaging times were both determined to be 1 day. The R2-dose response was linear to 4000cGy. The response of the MAGICA gel is very similar in the lower dose region and The R2-dose response for doses less than 250cGy is not exact. The R2-dose response of the MAGICA polymer gel dosimeter is linear between 500 to 1750 cGy with R2-dose sensitivities of 0.0020 and 0.0023S-1 cGy -1 when imaged at 1and 8 days post-irradiation respectively. In this study, the percentage depth dose (PDD) of MAGICA polymer gel dosimeter is determined and different phantoms of MAGICA gels was irradiated to 1000cGy of doses by 6, 8, 12 and 18MeV electrons and The maximum percentage depth dose (PDD) is located at the depths of 0.5, 1, 2 and 3cm. © 2009 IOP Publishing Ltd.