|Message: Re: optical photons and G4VPVParameterisation||Not Logged In (login)|
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I traced down the problem. It was the REFLECTIVITY I assigned to the the quartz->scintillator border. I thought that REFLECTIVITY is the fraction of incident electromagnetic power that is reflected at an interface. Searching through the earlier questions on this forum I realised that it is true for a dielectric_metal surface but not for a dielectric_dielectric surface (which I have). Once I set the value of REFLECTIVITY for my boundary to be ONE I started getting consistent results.
But that leads me to a new question:
When I use G4PVPlacement my results are unaffected by value of REFLECTIVITY I supply. I tried: 0, 1, 0.5, and the number of absorbed, absorbed on boundary and photons exiting the calorimeter where the same. (I double checked if I recompiled the code after changing reflectivity)
When I use G4VPVParameterisation that is not a case. When set to a value close to ZERO, I had a few photons exiting calorimeter, and when set to ONE, the number was close to the one obtained with a setup using G4PVPlacement.
(I'm using geant4.9.6.p03)