|Message: Energy deposition in voxelized volume differs from continuous volumes||Not Logged In (login)|
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I'm having a problem on which I have been working several weeks now and nothing seems to work. I hope that somebody can help me out, because my creativity is running out and I still have no idea what can be the problem.
The energy distribution in a volume consisting of parameterized voxels seems to differ from the distribution in a continuous volume, with the same dimensions. This problem resembles the one of forum entry 233, but it wasn't solved then.
In trying to solve the problem, I reduced it to the following situation: I tested a 1 x 1 x 4 cm (5 x 5 x 20 voxel) parameterized water phantom and compared the energy distribution of a pencil beam with the energy distribution in a G4Box of the same dimensions, overlayered with a ROG with the same voxel dimensions. The energy distributions are different. For example, the energy deposition in the parameterized phantom did not show a dip at the end of the phantom, like one would expect due to the lack of backscattering electrons. Also, the continuous phantom has higher energy deposition values along the central axis. The total deposited energy in the phantom is the same for both situations.
I tried scoring on the basis of copyNo, ROG indices and even on the basis of the middle of the step in world coordinates.
I tried so many things more, but my posting would become frighteningly long if I would write it all down. for now I would just like to know whether this problem is known or if somebody has an idea what can be the problem. Thank you, in advance.
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