|Message: Angular distribution of neutrons following a gamma-n reaction||Not Logged In (login)|
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I'm simulating a photons bremsstrahlung spectrum up to 15 MeV against a target made of lead (G4_Pb) and I'm collecting data about neutrons produced. Using:
track -> GetVertexMomentumDirection()
I obtain a vector representing x/y/z components of the momenta at track vertex. (more precise I obtain cosine of the angular components).
If I put my data in an histogram I obtain the attached plots for each component. I conclude that produced neutrons are almost isotropic.
The question is: is this behavior correct? In physics reference manual I can't find any explanation of the angular distribution of products after a photon-nuclear reaction.
browsing the forum I found almost the same question here but no clear answer: http://hypernews.slac.stanford.edu/HyperNews/geant4/get/hadronprocess/1220.html
Thank you and best regards
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