Re: Antiproton annihilation cross section

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Re: Antiproton annihilation cross section

Dear, Vladimir,

Thank you very much for answering. Well, I was not using default PhysicsLists, I've made up my own. As for antiprotons, defined processes are:

        else if (particleName == "anti_proton")
          {
             pmanager->AddDiscreteProcess(theElasticProcess);

             G4AntiProtonInelasticProcess* theInelasticProcess =
               new G4AntiProtonInelasticProcess();

             G4LEAntiProtonInelastic* theLEInelasticModel =
                    new G4LEAntiProtonInelastic;
             theLEInelasticModel->SetMaxEnergy(20.0*GeV);
             theInelasticProcess->RegisterMe(theLEInelasticModel);

             pmanager->AddDiscreteProcess(theInelasticProcess);

             pmanager->AddRestProcess(new G4AntiProtonAnnihilationAtRest);

             pmanager->AddRestProcess(new G4QCaptureAtRest());
          }

and, of course, EM part:

        pmanager->AddProcess(new G4MultipleScattering(), -1, 1, 1);
        pmanager->AddProcess(new G4hIonisation(), -1, 2, 2);

Or maybe you are suggesting to use another models/processes for antiprotons?

Thank you,

 Kirill Skovpen

Re: Antiproton annihilation cross section by Vladimir Ivanchenko <Vladimir Ivanchenko>, 12 Apr, 2009 Re: Re: Antiproton annihilation cross section (Kirill Skovpen) Hello Kirill, Your Physics List is similar to the default which is using parameterized model (GHEISHA, derived from G3). There is a bug - you instantiate 2 AtRest processes - one obsolere G4AntiProtonAnnihilationAtRest and recommanded one G4QCaptureAtRest. I would remove the first one. To have better anti_proton physics you likely need to use other G4 models. I would let you communicate with original authors of FTF base models, QGS base models, CHIPS models and Bertini. They should clarify if any of above can be used now and at what energy. VI

Re: Antiproton annihilation cross section by Kirill Skovpen <Kirill Skovpen>, 16 Apr, 2009 Re: Re: Antiproton annihilation cross section (Vladimir Ivanchenko) Thank you Vladimir for your answer. Ok, I'll remove the bug concerned with duplicate of AnnihilationAtRest process and try to use other models(FTF,QGS,CHIPS,Bertini) to see if there any differences in antiproton simulation from the default PhysicsList for low energies.

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