Non-uniform Source Distribution

Source Definition
3

Dear Charubala,

  1. If you want to sample for separate organs with different activity, you need to assign different materials to them, and then you will be able to set the COMSCW variable in a way that the ratio of them would match the ratio of the specific activity of the organs.

  2. It should be possible: If the left and right lungs are separate ROIs then see point 1. If not then you may be able to separate the lungs by checking the coordinate of the energy deposition using the Xa, Ya and Za variables in the comscw.f user routine.

  3. The user routines are not compatible with USRBIN sources, but in general both options for sampling are valid.

Alternatively, you could simulate each organ separately, and combine the results using the usbscw command line program (See: USRBIN-multiply the results - #4 by horvathd). This would allow you to change the activity ratio of the organs without rerunning the whole simulation.

Cheers,
David

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