[Gate-users] dose actors - NaN values in Edep file

[Robin Palit]

Hello,

I am trying to determine the energy deposited within a voxel phantom by an
x-ray source.  I have setup a dose actor to report deposited energy within
each voxel of a phantom.  In the file that is output by Gate (dose-Edep.img)
there are several NaN values that are reported.  The location of these NaN
values are spread out over the phantom (i.e. do not appear to preferentially
distributed toward a certain tissue type). Has anyone run into this issue
before or have any ideas on why these NaN values are occurring?

The following is a brief description of my simulation.  The phantom was
created using NCAT, indexed by tissue type with an accompanying range.dat
table, and converted to the interfile format.  The source is a
mono-energetic 120 keV cone beam emanating from a point.  The physics
processes that are included are those from the physics.mac file from the
example_CT folder.  Posted below are the lines of code that I have used to
set up my dose actor.

/gate/actor/addActor DoseActor doseDist
/gate/actor/doseDist/save dose.hdr
/gate/actor/doseDist/attachTo phantom
/gate/actor/doseDist/stepHitType random
/gate/actor/doseDist/setPosition 0 0 0 mm
/gate/actor/doseDist/setSize 137.1123 600.0128 600.0128 mm
/gate/actor/doseDist/setVoxelSize 1.1719 1.1719 1.1719 mm
/gate/actor/doseDist/enableEdep true
/gate/actor/doseDist/enableUncertaintyEdep true

-Robin