Dosimetric study of GZP6 (60)Co high dose rate brachytherapy source

The purpose of this study was to obtain dosimetric parameters of GZP6 (60)Co brachytherapy source number 3. The Geant4 MC code has been used to obtain the dose rate distribution following the American Association of Physicists in Medicine (AAPM) TG‐43U1 dosimetric formalism. In the simulation, the source was centered in a 50 cm radius water phantom. The cylindrical ring voxels were 0.1 mm thick for r ≤ 1 cm, 0.5 mm for 1 cm < r ≤ 5 cm, and 1 mm for r > 5 cm. The kerma‐dose approximation was performed for r > 0.75 cm to increase the simulation efficiency. Based on the numerical results, the dosimetric datasets were obtained. These results were compared with the available data of the similar (60)Co high dose rate sources and the detailed dosimetric characterization was discussed.