Photoneutron detection

Dear all,

In my simulation I am shooting gamma photons of different energies (higher than 15 MeV) at a carbon shielding slab (volume in white), which in theory should produce photoneutrons, which then I would detect in a water sphere sensitive detector (volume in blue), as showed in the following image:

Unfortunately, no photoneutrons are being produced. I have tested detecting other particles and everything works fine, I double checked this by activating the Verbose and indeed no photodisintegration processes were listed. I have tried different materials, such as tungsten or other high-Z materials, as well as higher gamma energy photons and increasing the number of samples up to a couple of millions but still no photoneutrons are being produced.

Perhaps the problem is related to the Physics Lists? These are the ones that I am using in my simulation:

  • THE FOLLOWING ELECTROMAGNETIC PHYSICS LIST HAS BEEN ACTIVATED: G4EmLivermorePhysics
  • THE FOLLOWING ELECTROMAGNETIC PHYSICS LIST HAS BEEN ACTIVATED: G4EmStandardPhysics_option3
  • THE FOLLOWING HADRONIC INELASTIC PHYSICS LIST HAS BEEN ACTIVATED: HadronPhysicsQGSP_BIC_HP()
  • THE FOLLOWING HADRONIC INELASTIC PHYSICS LIST HAS BEEN ACTIVATED: G4IonBinaryCascadePhysics()
  • THE FOLLOWING HADRONIC INELASTIC PHYSICS LIST HAS BEEN ACTIVATED: G4RadioactiveDecayPhysics()
  • G4PhysListFactory::GetReferencePhysList <QGSP_BERT_HP> EMoption= 0
    <<< Geant4 Physics List simulation engine: QGSP_BERT_HP
    <<< Reference Physics List QGSP_BERT_HP is built

I am using Geant4 10.5.0 version.

Any help with this matter would be greatly appreciated.

Thank you in advance!

Hi Efraín
I suggest you post this on the Physics Processes Forum.
John

1 Like

Thanks for your suggestion. I just did.

you must add G4EmExtraPhysics

1 Like

Thank you, Maire! Photoneutron production is working now :grinning: