|Message: Overlap of parameterized volumes||Not Logged In (login)|
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I have a question concerning the overlap of two volumes: One containes parameterised volumes and the second not.
The reason is PET (Positron emission tomography):
Positrons are started in the "patient" that is voxelized (!= smart voxels). The patient is situated in a cylinder of shielding and detectors.
The patient is described by parameterised volumes, the shielding not. The patient is described by rectangular voxels. Rectangular voxels cannot fit seamlessly into a cylinder, therefore the patient is described by a sourrounding G4Box with parameterized G4Boxes inside. In order to have a realistically sized patient (which is rather elliptic) and scanner the corners of the surrounding G4Box must overlap with the shielding. In the overlapped part of the patient is only air.
Is the behaviour of Geant4 in such a case defined? And if not, is it possible to use a surrounding G4Tubs instead of the G4Box while still keeping rectangular parameterized volumes inside?
Thank you very much
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