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Forum: Hadronic Processes
Re: Question protons from neutrons (Andrea Di Simone)
Date: 23 Feb, 2010
From: Dennis H. Wright <Dennis H. Wright>

Hi Andrea,

  What you report is not expected behavior, so I'm guessing you have uncovered a bug.  What is not clear to me from your traceback is whether elastic or inelastic scattering is occuring.   At first glance it looks like repeated
elastic scatters of neutrons from hydrogen in which the recoil is not taken into account, thereby keeping the energy deposit at zero.  In this case your 
material would have to be hydrogen.
  In order to proceed, could you provide the following:
1) the material the neutron is traveling in
2) the process which defined the step, that is, whether elastic or inelastic scattering is happening.   If it is not already in your traceback somewhere
you can get it by invoking the method GetProcessDefinedStep()from the pointer to the post-step point in your user stepping action.   Otherwise I can
set up a test to find it.

  As to what is going on, I can only speculate at this point.  If it is elastic
scattering, there may be an incorrect Lorentz boost (or lack of one).  If it is
inelastic scattering the precompound/evaporation stage of the Bertini model would handle neutrons of this energy (0.62 MeV).  A coulomb barrier was added in version 9.2, so there should be no protons generated below about 8 MeV. Also, because the energy is quite low the model may make some rather crude assumptions about what to do when producing secondaries.

Dennis

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1 None: Re: protons from neutrons   (Andrea Di Simone - 24 Feb, 2010)
(_ None: Re: protons from neutrons   (Andrea Di Simone - 03 Mar, 2010)
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