[Gate-users] No projection data from phase space source

[Miriam Dixon]

Hi Gate users,

In order to save time in running my simulation, I am trying to set up a
phase space file (PSF) that I can use as the source. The simulation is a
SPECT system, with the PSF attached to an STL heart geometry. The problem I
am having is that when the PSF is read as the source, there is only a
couple of pixels present in the projection data at the completion of the
simulation, rather than the full image produced when the STL heart had the
source confined to it.

I used Root to inspect the created .root PSF and it appears to be fine, and
when the simulation is visualized, photons (in the form of green lines)
appear, centered at the heart as expected.

The code for writing the PSF is:
/gate/actor/addActor                         PhaseSpaceActor PhS_g
/gate/actor/PhS_g/attachTo                   heart
/gate/actor/PhS_g/useVolumeFrame             true
/gate/actor/PhS_g/save
output/PhS-Gamma-{HEART}-{ACTIVITY}MBq.root
/gate/actor/PhS_g/storeOutgoingParticles     true
/gate/actor/PhS_g/enableParticleName         false
/gate/actor/PhS_g/enableProductionVolume     false
/gate/actor/PhS_g/enableProductionProcess    false
/gate/actor/PhS_g/useVolumeFrame             true   #Not using world
coordinates
/gate/actor/PhS_g/addFilter                  particleFilter
/gate/actor/PhS_g/particleFilter/addParticle gamma
/gate/actor/PhS_g/enableZPosition            true

And for reading it again as the source in a second simulation:
/gate/source/addSource                            src_Heart phaseSpace
/gate/source/src_Heart/addPhaseSpaceFile
 data/PhSData/PhS-Gamma-{HEART}-{ACTIVITY}MBq.root
/gate/source/src_Heart/setParticleType            gamma
/gate/source/src_Heart/attachTo                   heart
/gate/source/src_Heart/useRandomSymmetry          true

/gate/source/src_Heart/setForcedHalfLife  21624.12 s  #6.0 hrs
/gate/source/src_Heart/setForcedUnstableFlag true
/gate/source/src_Heart/setActivity {ACTIVITY} MBq

The heart STL file used is the same in each piece of code.
Because the .root file appears well populated, I expect the problem is with
implementing the file as a source but have not yet found the solution.

Any advice will be appreciated.
Cheers,
Miriam
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