|Message: Re: How does G4 deal with the overlap energy range between the different physical models?||Not Logged In (login)|
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Dear Liyong, When two models overlap in energy, the "trick" Geant4 uses is to randomly select one or the other, with a probability which is linear with energy : that is, if the energy is close to model A, model A will be used often; if the energy is in the middle of the energy range overlap, then models A and B will be chosen in 50% of the cases each; and when the energy is very close to model B, model B will almost always be used. Of course, this is not perfect, but a correct treatment would require a model that would be able to handle the overlap between the two energy regimes, meaning that, likely, this model would be advanced enough to handle the total energy range of these two regimes. Cheers, Marc On 12/07/2016 05:09, liyong wrote: > *** Discussion title: Physics List > > Dear all, > > I include the physical processes "G4HadronPhysicsQGSP_BIC_HP" in my > simulation and it shows me that the model "Binary Cascade", "FTFP" and > "QGSP" play major roles in the energy range of incident proton of 0MeV - > 9.9GeV, 9.5GeV - 25GeV and 12GeV - 100TeV, respectively. I want to know > how does G4 deal with the overlap energy range between the different > physical models? For example, if the energy range of incident proton is > 9.5-9.9GeV, which physical model to choose in G4? > > Thank you in advance! > > Liyong > > ------------------------------------------------------------- > Visit this GEANT4 at hypernews.slac.stanford.edu message (to reply or unsubscribe) at: > http://hypernews.slac.stanford.edu/HyperNews/geant4/get/phys-list/940.html
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