Scintillation enhanced time constants

Particles, Track, Event, Run and Biasing
1

Hello!
I am using the 10.07 version of Geant4 and implementing the enhanced time constants for my scintillator material (three time constants). As my scintillator is capable of pulse shape discrimination, the time constants are different for neutrons and gamma rays, is there a way to specify the time constants for the different particles?
Thank you.

2

Hi,

You can adjust the weights for the different channels. For example first set two time constants for all particles, then set the particle-specific yield for each channel. In this example protons will have time constant 1 ns and alpha will have time constant 10 ns.

myMPT1->AddConstProperty("SCINTILLATIONTIMECONSTANT1", 1. * ns);
myMPT1->AddConstProperty("SCINTILLATIONTIMECONSTANT2", 10. * ns);
myMPT1->AddConstProperty("PROTONSCINTILLATIONYIELD1", 1);
myMPT1->AddConstProperty("PROTONSCINTILLATIONYIELD2", 0);
myMPT1->AddConstProperty("ALPHASCINTILLATIONYIELD1", 0);
myMPT1->AddConstProperty("ALPHASCINTILLATIONYIELD2", 1);

Also, note that there was a bug in which neutral particles did not produce scintillation photons. It will be available in the next patch and beta releases. Alternatively if you can modify the source, change the IsApplicable method in
source/processes/electromagnetic/xrays/src/G4Scintillation.cc
to:

G4bool G4Scintillation::IsApplicable(const G4ParticleDefinition& aParticleType)
{
  if (aParticleType.GetParticleName() == "opticalphoton")
    return false;
  if (aParticleType.IsShortLived())
    return false;
  return true;
}