A Monte Carlo approach for dose prediction tools in gamma irradiator: The effect of resolution on measurement

The uniformity of dose distribution within the irradiation chamber is critical, but it becomes more difficult in varied-dimensional chambers, which might result in a heterogeneous total dose distribution. Determining the absorbed dose of radiation correctly is regulated in a standard protocol to ensure accurate measurements and can produce reproducibility in the radiation process. These studies address the challenge of dose measurement by developing an effective method to obtain accurate radiation dose distribution with adequate resolution, thereby reducing the need for a large number of dosimeters. This approach ensures statistical alignment with measurement results, thereby overcoming limitations in efficiency and accuracy. The object used in this project is a Gamma Cell 220. Alanine dosimeter and film (Gafchromic) are used as measurements in the experiment. Meanwhile, Monte Carlo simulation uses The Particle and Heavy Ion Transport Code System (PHITS). A comparison of relative dose differences was used as the basis for the agreement between simulation and experiment. In the range of 100 Gy to 60 kGy, the relative agreement was 2.4 %. A t -test was then used to compare the two resolutions, simulation and film measurements, to demonstrate the correlation between the two results. The results revealed that the relatively small area between 7.5 cm and 12.5 cm on the Z-axis from the bottom is the most homogeneous. It should be noted that the area has a radius of no more than 5 cm. The results of experiments using alanine and film dosimeters and their comparison with Monte Carlo simulations show differences in terms of resolution.