Simulation of absorbed dose rate for apple in a gamma cell 220 device using MCNPX code

In this study, the dose rates in a gamma cell 220 device for apple were calculated by using MCNPX code in two states. In first state, apple uniformly fills the whole space of gamma cell. In second state, it was supposed that apples are spherical form that the empty space between them is filled by air. Generally, the results show that in both states the distributed dose rates are non-uniform. In first state, the values of dose rates for apple are less than air but are same for water. In the center of device, the dose rates for apple and air are 2.85 and 3.35 Gy/s , respectively while in the top or bottom of deceive,dose rates are 1.5 and 2.5 Gy/s. In the second state, the dose rate variations are between 3.06 Gy/s for central apple and 4.1 Gy/s for neighbor apples. In comparison with delivered mean dose rate by device (3.05±0.04 Gy/s), the variation of dose rate for central apple is negligible while for neighbor apples it increases to 30%. Thus, this difference can affect the physical and chemical properties of the watery fruits.