Neutron Inelastic Scattering

Validation and Verification
1

HI everyone,

The doc is a little unclear to me : What happen to neutron having inelastic scattering reaction ? Does the code continue the tracking of the neutron out ? Is it considered like a new neutron (new track) or the continuation of the same track as the input neutron. How is it taken into account in the kcoll estimator ?

When I compare my openmc results with my own Geant4 code, I have a slight difference (1%) on the keff. But in my G4 code, I simulate neutrons coming out of inelastic scattering reactions in the same batch with the same track. I have around 1% of produced inelastic neutrons in my test case so I assume the difference may come from there.

I use ENDF8 for for codes.

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Update : My model has a lot of carbon in it. After some research, I found that special models must be used when modeling neutron carbon interaction → Low Energy Charged Particle Interactions — Physics Reference Manual 11.2 documentation

Is that model used in openmc ? I found nothing in the documentation.

3

Hi Ferney,

yes/no, OpenMC only simulates transport of neutrons and photons.

The loss term of the neutron will be accounted for, but charged particles will not be produced and transported. (tritons, alphas, etc)
https://www.nrc.gov/docs/ML1122/ML11229A705.pdf

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