Maybe a bug, why the material of LogicalVolume is not changed?

Geometry, Fields and Transportation
1

I used DetectorMessenger class to change the solid size and the material of LogicalVolume, when one command line was used, evergything worked ok. But, when the two command lines were used, the material of LogicalVolume could not be changed.

when using one command line “/fp/det/setTargetMaterial G4_WATER”, here is the hint from the session:
========= Table of registered couples ============================

Index : 0 used in the geometry : Yes
Material : G4_Galactic
Range cuts : gamma 700 um e- 700 um e+ 700 um proton 0 fm
Energy thresholds : gamma 990 eV e- 990 eV e+ 990 eV proton 0 eV
Region(s) which use this couple :
DefaultRegionForTheWorld

Index : 1 used in the geometry : No
Material : G4_Pb
Range cuts : gamma 700 um e- 700 um e+ 700 um proton 0 fm
Energy thresholds : gamma 94.5861 keV e- 1.00386 MeV e+ 951.321 keV proton 0 eV

Index : 2 used in the geometry : Yes
Material : G4_WATER
Range cuts : gamma 700 um e- 700 um e+ 700 um proton 0 fm
Energy thresholds : gamma 2.51944 keV e- 276.265 keV e+ 270.751 keV proton 0 eV
Region(s) which use this couple :
DefaultRegionForTheWorld

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

oooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo
from the hint, the material was changed from G4_Pb to G4_WATER
oooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo

when using the two command lines “/fp/det/setTargetMaterial G4_WATER” and “/fp/det/setSize 10 cm”, here is the hint from the session:
========= Table of registered couples ============================

Index : 0 used in the geometry : Yes
Material : G4_Galactic
Range cuts : gamma 700 um e- 700 um e+ 700 um proton 0 fm
Energy thresholds : gamma 990 eV e- 990 eV e+ 990 eV proton 0 eV
Region(s) which use this couple :
DefaultRegionForTheWorld

Index : 1 used in the geometry : Yes
Material : G4_Pb
Range cuts : gamma 700 um e- 700 um e+ 700 um proton 0 fm
Energy thresholds : gamma 94.5861 keV e- 1.00386 MeV e+ 951.321 keV proton 0 eV
Region(s) which use this couple :
DefaultRegionForTheWorld

==================================================================
oooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo
from the hint, the material was still G4_Pb
oooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo

it is so strange, why?

1 Like
2

It’s impossible to tell without seeing the code and relevant calls for the detector constructor class and the messenger that accompanies it. I would guess there is some ordering/missing call somewhere, or yes, a genuine bug.