Thermal neutron dose evaluation using MAGICA polymer gel dosimeter

Abstract

Polymer gel dosimeters are fabricated from radiation sensitive chemicals which, upon irradiation, polymerize as a function of the absorbed radiation dose. In this research stiffness of MAGIC gel dosimeter improved by addition of agarose and was named MGICA. MAGICA gel dosimeter irradiated by moderated fission neutrons in Tehran Research Reactor (TRR) thermal column, and the response of gel was investigated as variation of spin-spin relaxation rate in MR image of gel phantoms. The linearity of the response (R2) versus absorbed dose (D), sensitivity, dose resolution and minimum detectable dose (MDD) were investigated. For calibration of gel response versus dose, foil activation analysis was performed. A cadmium covered gold foil was placed at the end of column (nearest to core) to ensure avoidance of non thermal neutrons in the thermal column. Sensitivity and MDD of MAGICA gel dosimeter for thermal neutron were 0.17 ± 0.01 Gy^− 1s^− 1 and 1.2 Gy respectively. From this study it concluded that MAGICA gel dosimeter is a capable instrument for ther-mal neutron dosimetry.