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None Photonuclear with Bertini in g4.10.00.p01 

Forum: Hadronic Processes
Date: 30 May, 2014
From: Dario Lattuada <Dario Lattuada>

Hi, I'm new to G4 and I'm trying to use it to study nuclear reactions, especially the photodisintegration of light nuclei at low energies. I read that this topic is rather new for Geant and not everything works 100%.

Anyway I used example Hadr03 as a starting point with:

  G4ProcessManager* pManager = G4Gamma::Gamma()->GetProcessManager();
   //
    G4PhotoNuclearProcess* process = new G4PhotoNuclearProcess();
   process->BiasCrossSectionByFactor(1000000000);
   //
   G4CascadeInterface* bertini = new G4CascadeInterface();
   bertini->SetMaxEnergy(10*GeV);
   process->RegisterMe(bertini);
   //
   pManager->AddDiscreteProcess(process);

to study 24Mg(gamma,alpha)20Ne reaction at 11MeV.

So I run a 11MeV gamma beam on a Mg24 target but unfortunately I only get neutrons and protons (the latter only with slightly higher gamma energy) but no alphas until some 20ish MeV where everything is ok and correct Q-Value is also printed in the summary at the end of the run. I tried to go deep into G4CascadeInterface() but it's very complicated and unclear to me which models and classes handle the whole process. I suspect it might be related to some other threshold or internal check, maybe something with the CoulombBarrier but it's just a guess and so far no workaround solved it.

Can someone please provide some useful information about classes and methods involved in the process I want to study? Am I doing something wrong? Does anyone work with these classes and/or did develop some new code? Any other suggestion would be very appreciated!

Thank you

Dario

note: I hacked into the code and implemented the BiasCrossSectionByFactor method for G4PhotoNuclearProcess (it couldn't find the method, I just copied it from ), and changed the threshold energy by considering alpha emission in calculation, by replacing the return value of G4PhotoNuclearCrossSection::ThresholdEnergy as:

   return (dA < dP ? (dA < dN ? dA : dN) : (dP < dN ? dP : dN));

where dA is related to alpha emission. And that provided the first neutrons out of the target.

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1 None: Re: Photonuclear with Bertini in g4.10.00.p01   (Dario Lattuada - 07 Jul, 2014)
2 None: Re: Photonuclear with Bertini in g4.10.00.p01   (Dennis H. Wright - 18 Jul, 2014)
1 None: Re: Photonuclear with Bertini in g4.10.00.p01   (Dario Lattuada - 21 Jul, 2014)
(_ None: Re: Photonuclear with Bertini in g4.10.00.p01   (Dario Lattuada - 25 Jul, 2014)
(_ None: Re: Photonuclear with Bertini in g4.10.00.p01   (Michael H. Kelsey - 25 Jul, 2014)
(_ None: Re: Photonuclear with Bertini in g4.10.00.p01   (Dario Lattuada - 29 Jul, 2014)
1 None: Re: Photonuclear with Bertini in g4.10.00.p01 (ERRATA CORRIGE)   (Dario Lattuada - 29 Jul, 2014)
2 None: Re: Photonuclear with Bertini in g4.10.00.p01   (Dennis H. Wright - 31 Jul, 2014)
... 3 Message(s)
3 Idea: Re: Photonuclear with Bertini in g4.10.00.p01   (Vladimir Ivanchenko - 02 Aug, 2014)
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