|Message: Giant Dipole Resonance photo-neutron production in medical linac||Not Logged In (login)|
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I want to simulate the spectrum of neutrons produced inside e medical linac due to Giant Dipole Resonance. I have simulated the linac tungsten target, the primary and the secondary tungsten collimators and a 18 MeV electron source directed to the target.
At the moment I have loaded the FTFP_BERT_HP physics list and I have replaced the G4EmStandardPhysics builder of the list with the G4EmStandardPhysics_opt3 which, according to the physics list page of geant4, is optimized for medical applications.
I have started the simulation, but almost no neutrons are produced. After some digging I have discovered that the Giant Dipole Resonance process is described by a G4PhotoNuclearProcess, and the corresponding model is G4GammaNuclearReaction. Unfortunately, looking at the FTFP_BERT_HP and G4EmStandardPhysics_opt3 builders I can't see this process activated for gammas.
Am I missing something? After a particle/process/dump for gammas I can see that some kind of HadronInelastic process is activated, but I don't understand what process it is...
Thanks for your help and suggestions!
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