Error while CBCT simulation with Geant4

Dear Expertise,

I’m a newbie in this field , Please help to correct my errors. I was working on CBCT(Cone Beam CT) Simulation using Gate. I trying to run a macro code and while initialize it encounter some errors

-------- WWWW ------- G4Exception-START -------- WWWW -------
*** G4Exception : modeling0015
issued by : G4PhysicalVolumeModel::Validate
Attempt to validate a volume that is no longer in the physical volume store.
*** This is just a warning message. ***
-------- WWWW -------- G4Exception-END --------- WWWW -------

WARNING: Model “G4PhysicalVolumeModel world_phys:0 BasePath: TOP” is no longer valid - being removed
from scene “scene-0”

i Would also share the main macro code.

#=====================================================

VERBOSITY

#=====================================================

/control/execute mac/verbose.mac

=====================================================

GEOMETRY

=====================================================

-----------------------------------------------------

World

/gate/geometry/setMaterialDatabase data/GateMaterials.db
/gate/world/setMaterial Air
/gate/world/geometry/setXLength 3 m
/gate/world/geometry/setYLength 3 m
/gate/world/geometry/setZLength 3 m

Box: Gantry

/gate/world/daughters/name Gantry
/gate/world/daughters/insert box
/gate/Gantry/geometry/setXLength 2 m
/gate/Gantry/geometry/setYLength 2 m
/gate/Gantry/geometry/setZLength 2 m
/gate/Gantry/setMaterial Air
/gate/Gantry/vis/setVisible 1
/gate/Gantry/vis/setColor yellow

#Box: Detection Plane
/gate/Gantry/daughters/name DetectorPlane
/gate/Gantry/daughters/insert box
/gate/DetectorPlane/geometry/setXLength 1409.6 mm
/gate/DetectorPlane/geometry/setYLength 1409.6 mm
/gate/DetectorPlane/geometry/setZLength 10 mm
/gate/DetectorPlane/placement/setTranslation -536 0 0 mm
/gate/DetectorPlane/setMaterial Air
/gate/DetectorPlane/vis/setVisible 1
/gate/DetectorPlane/vis/setColor yellow

Box: FOV

#/gate/Gantry/daughters/name FOV
#/gate/Gantry/daughters/insert box
#/gate/FOV/geometry/setXLength 0.8 m
#/gate/FOV/geometry/setYLength 0.8 m
#/gate/FOV/geometry/setZLength 0.8 m
#/gate/FOV/setMaterial Air
#/gate/FOV/vis/setVisible 1
#/gate/FOV/vis/setColor green

Rotation of FOV

#/gate/FOV/placement/setRotationAxis 0 1 0
#/gate/FOV/placement/setRotationAngle 0 deg

-----------------------------------------------------

HU Materials

/gate/HounsfieldMaterialGenerator/SetMaterialTable data/Schneider2000MaterialsTable.txt
/gate/HounsfieldMaterialGenerator/SetDensityTable data/Schneider2000DensitiesTable.txt
/gate/HounsfieldMaterialGenerator/SetDensityTolerance 0.2 g/cm3
/gate/HounsfieldMaterialGenerator/SetOutputMaterialDatabaseFilename data/patient-HUmaterials.db
/gate/HounsfieldMaterialGenerator/SetOutputHUMaterialFilename data/patient-HU2mat.txt
/gate/HounsfieldMaterialGenerator/Generate

-----------------------------------------------------

Patient

/gate/Gantry/daughters/name patient #FOV to Gantry
/gate/Gantry/daughters/insert ImageNestedParametrisedVolume #FOV to Gantry
/gate/geometry/setMaterialDatabase data/patient-HUmaterials.db
/gate/patient/geometry/setHUToMaterialFile data/patient-HU2mat.txt
/gate/patient/geometry/setImage data/patient-lung-2mm.mhd
/gate/patient/geometry/TranslateTheImageAtThisIsoCenter 4.6 30.9 -655.5 mm

#=====================================================

PHYSIC

#=====================================================

/gate/physics/addPhysicsList emstandard_opt1

/gate/physics/Gamma/SetCutInRegion world 10 mm
/gate/physics/Electron/SetCutInRegion world 10 mm
/gate/physics/Positron/SetCutInRegion world 10 mm

/gate/physics/Gamma/SetCutInRegion patient 10 mm

/gate/physics/Electron/SetCutInRegion patient 10 mm

/gate/physics/Positron/SetCutInRegion patient 10 mm

/gate/physics/SetMinRemainingRangeInRegion world 10 mm

/gate/physics/ActivateSpecialCuts e-

/gate/physics/displayCuts

#=====================================================

INITIALISATION

#=====================================================

/gate/run/initialize

#=====================================================

VISUALISATION

#=====================================================

/control/execute mac/visu.mac

#=====================================================

BEAM

#=====================================================

/gate/source/addSource mybeam gps
/gate/source/mybeam/attachTo Gantry
/gate/source/mybeam/gps/particle gamma
/gate/source/mybeam/gps/ene/type Mono
/gate/source/mybeam/gps/ene/mono 60 keV
/gate/source/mybeam/gps/pos/type Point
/gate/source/mybeam/gps/pos/halfx 8 mm
/gate/source/mybeam/gps/pos/halfy 8 mm
/gate/source/mybeam/gps/pos/centre 1060 0 0 mm
/gate/source/mybeam/gps/pos/rot1 0 1 0
/gate/source/mybeam/gps/pos/rot2 0 0 1
/gate/source/mybeam/gps/pos/type Plane
/gate/source/mybeam/gps/pos/shape Rectangle
/gate/source/mybeam/gps/direction -1 0 0
/gate/source/mybeam/gps/ang/type focused
/gate/source/mybeam/gps/ang/rot1 0 1 0
/gate/source/mybeam/gps/ang/rot2 0 0 1
/gate/source/mybeam/gps/ang/focuspoint 1000 0 0 mm

#=====================================================

DETECTORS

#=====================================================

Photon counting detector

/gate/actor/addActor FluenceActor DetectorActor
/gate/actor/DetectorActor/save output/detector.mhd
/gate/actor/DetectorActor/attachTo DetectorPlane
/gate/actor/DetectorActor/stepHitType post
#/gate/actor/DetectorActor/setSize 10 409.6 409.6 mm
/gate/actor/DetectorActor/setSize 10 500 500 mm
/gate/actor/DetectorActor/setResolution 1 100 100
/gate/actor/DetectorActor/enableScatter true
/gate/actor/DetectorActor/saveEveryNSeconds 20

Stat

/gate/actor/addActor SimulationStatisticActor stat
/gate/actor/DetectorActor/save output/detector.mhd

/gate/actor/stat/save output/stats.txt
/gate/actor/stat/saveEveryNSeconds 20

#=====================================================

MAIN

#=====================================================

DEBUG

#/tracking/verbose 1
#/tracking/verbose 1

/gate/random/setEngineName MersenneTwister
/gate/random/setEngineSeed auto

/gate/application/setTotalNumberOfPrimaries 10000
/gate/application/start

As this in GATE, and likely specific to their geometry construction commands/behaviour, I’d suggest posting to their support mailing list as you may get a quicker/better response there.