Did not sample any nuclide during collision

Hello,
I’m trying to run OPENMC in fixed source calculation mode using an external source file and this error occurred


Can someone tell me what happens?
Thanks,
Pattarapol

This is usually indicative of something wrong with cross section lookups. If you’re using an external source file, one possible problem is that the energies of your particles are not within the range over which cross sections are available. How are you setting the energies of your source particles in the source file?

1 Like

Hi All,

I have been getting this error after switching from the ENDF-B 8.0 cross section library to the FENDL 3.2b library. I got both libraries from Data Libraries | OpenMC. My source is a Muir distribution of 14.1 MeV neutrons. When I run OpenMC, I get the error:
RuntimeError: Did not sample any element during collision.

The problem is intermittent but seems to happen only when I have photon transport on. Is there a way to pick the ENDF-B photon cross sections but the FENDL neutron cross sections? Or another way to handle this issue?

Thank you!

Hi All,

You can of course edit the cross_sections.xml file to pick a combination of cross sections. That’s what I’ve chosen to do. Thanks!

@kevinm387 What nuclides did you have in your problem when you experienced that error? I’d like to see if I can reproduce and perhaps implement a better error check for this situation. If you’re able to share your model, that would be even better.

Hi Paul,

Unfortunately I can’t share the model, but below are all the nuclides used in the problem. Apologies that it is quite long. The problem is intermittent (in fact, as I’m typing this I’m struggling to reproduce it) but seemed to go away when I use ENDFB 8.0 cross sections for photons.

I could create an analogous model if it would be helpful. Thank you for looking into this!

Reading Y89 from
/xs_libraries/fendl-3.2-hdf5/neutron/Y89.h5
Reading Y from
/xs_libraries/fendl-3.2-hdf5/photon/Y.h5 
Reading Ba130 from
/xs_libraries/fendl-3.2-hdf5/neutron/Ba130.h5
Reading Ba from
/xs_libraries/fendl-3.2-hdf5/photon/Ba.h5 
Reading Ba132 from
/xs_libraries/fendl-3.2-hdf5/neutron/Ba132.h5
Reading Ba137 from
/xs_libraries/fendl-3.2-hdf5/neutron/Ba137.h5
Reading Ba138 from
/xs_libraries/fendl-3.2-hdf5/neutron/Ba138.h5
Reading Ba135 from
/xs_libraries/fendl-3.2-hdf5/neutron/Ba135.h5
Reading Ba136 from
/xs_libraries/fendl-3.2-hdf5/neutron/Ba136.h5
Reading Ba134 from
/xs_libraries/fendl-3.2-hdf5/neutron/Ba134.h5
Reading Cu65 from
/xs_libraries/fendl-3.2-hdf5/neutron/Cu65.h5
Reading Cu from
/xs_libraries/fendl-3.2-hdf5/photon/Cu.h5 
Reading Cu63 from
/xs_libraries/fendl-3.2-hdf5/neutron/Cu63.h5
Reading O16 from
/xs_libraries/fendl-3.2-hdf5/neutron/O16.h5
Reading O from
/xs_libraries/fendl-3.2-hdf5/photon/O.h5 
Reading O17 from
/xs_libraries/fendl-3.2-hdf5/neutron/O17.h5
Reading O18 from
/xs_libraries/fendl-3.2-hdf5/neutron/O18.h5
Reading W184 from
/xs_libraries/fendl-3.2-hdf5/neutron/W184.h5
Reading W from
/xs_libraries/fendl-3.2-hdf5/photon/W.h5 
Reading W182 from
/xs_libraries/fendl-3.2-hdf5/neutron/W182.h5
Reading W180 from
/xs_libraries/fendl-3.2-hdf5/neutron/W180.h5
Reading W183 from
/xs_libraries/fendl-3.2-hdf5/neutron/W183.h5
Reading W186 from
/xs_libraries/fendl-3.2-hdf5/neutron/W186.h5
Reading H2 from
/xs_libraries/fendl-3.2-hdf5/neutron/H2.h5
Reading H from
/xs_libraries/fendl-3.2-hdf5/photon/H.h5 
Reading H1 from
/xs_libraries/fendl-3.2-hdf5/neutron/H1.h5
Reading Pb206 from
/xs_libraries/fendl-3.2-hdf5/neutron/Pb206.h5
Reading Pb from
/xs_libraries/fendl-3.2-hdf5/photon/Pb.h5 
Reading Pb204 from
/xs_libraries/fendl-3.2-hdf5/neutron/Pb204.h5
Reading Pb207 from
/xs_libraries/fendl-3.2-hdf5/neutron/Pb207.h5
Reading Pb208 from
/xs_libraries/fendl-3.2-hdf5/neutron/Pb208.h5
Reading Li6 from
/xs_libraries/fendl-3.2-hdf5/neutron/Li6.h5
Reading Li from
/xs_libraries/fendl-3.2-hdf5/photon/Li.h5 
Reading Li7 from
/xs_libraries/fendl-3.2-hdf5/neutron/Li7.h5
Reading H3 from
/xs_libraries/fendl-3.2-hdf5/neutron/H3.h5
Reading C12 from
/xs_libraries/fendl-3.2-hdf5/neutron/C12.h5
Reading C from
/xs_libraries/fendl-3.2-hdf5/photon/C.h5 
Reading C13 from
/xs_libraries/fendl-3.2-hdf5/neutron/C13.h5
Reading Si28 from
/xs_libraries/fendl-3.2-hdf5/neutron/Si28.h5
Reading Si from
/xs_libraries/fendl-3.2-hdf5/photon/Si.h5 
Reading Si30 from
/xs_libraries/fendl-3.2-hdf5/neutron/Si30.h5
Reading Si29 from
/xs_libraries/fendl-3.2-hdf5/neutron/Si29.h5
Reading P31 from
/xs_libraries/fendl-3.2-hdf5/neutron/P31.h5
Reading P from
/xs_libraries/fendl-3.2-hdf5/photon/P.h5 
Reading S36 from
/xs_libraries/fendl-3.2-hdf5/neutron/S36.h5
Reading S from
/xs_libraries/fendl-3.2-hdf5/photon/S.h5 
Reading S34 from
/xs_libraries/fendl-3.2-hdf5/neutron/S34.h5
Reading S33 from
/xs_libraries/fendl-3.2-hdf5/neutron/S33.h5
Reading S32 from
/xs_libraries/fendl-3.2-hdf5/neutron/S32.h5
Reading Cr50 from
/xs_libraries/fendl-3.2-hdf5/neutron/Cr50.h5
Reading Cr from
/xs_libraries/fendl-3.2-hdf5/photon/Cr.h5 
Reading Cr52 from
/xs_libraries/fendl-3.2-hdf5/neutron/Cr52.h5
Reading Cr54 from
/xs_libraries/fendl-3.2-hdf5/neutron/Cr54.h5
Reading Cr53 from
/xs_libraries/fendl-3.2-hdf5/neutron/Cr53.h5
Reading Mn55 from
/xs_libraries/fendl-3.2-hdf5/neutron/Mn55.h5
Reading Mn from
/xs_libraries/fendl-3.2-hdf5/photon/Mn.h5 
Reading Fe58 from
/xs_libraries/fendl-3.2-hdf5/neutron/Fe58.h5
Reading Fe from
/xs_libraries/fendl-3.2-hdf5/photon/Fe.h5 
Reading Fe57 from
/xs_libraries/fendl-3.2-hdf5/neutron/Fe57.h5
Reading Fe56 from
/xs_libraries/fendl-3.2-hdf5/neutron/Fe56.h5
Reading Fe54 from
/xs_libraries/fendl-3.2-hdf5/neutron/Fe54.h5
Reading Ni64 from
/xs_libraries/fendl-3.2-hdf5/neutron/Ni64.h5
Reading Ni from
/xs_libraries/fendl-3.2-hdf5/photon/Ni.h5 
Reading Ni58 from
/xs_libraries/fendl-3.2-hdf5/neutron/Ni58.h5
Reading Ni60 from
/xs_libraries/fendl-3.2-hdf5/neutron/Ni60.h5
Reading Ni62 from
/xs_libraries/fendl-3.2-hdf5/neutron/Ni62.h5
Reading Ni61 from
/xs_libraries/fendl-3.2-hdf5/neutron/Ni61.h5
Reading Mo97 from
/xs_libraries/fendl-3.2-hdf5/neutron/Mo97.h5
Reading Mo from
/xs_libraries/fendl-3.2-hdf5/photon/Mo.h5 
Reading Mo96 from
/xs_libraries/fendl-3.2-hdf5/neutron/Mo96.h5
Reading Mo98 from
/xs_libraries/fendl-3.2-hdf5/neutron/Mo98.h5
Reading Mo100 from
/xs_libraries/fendl-3.2-hdf5/neutron/Mo100.h5
Reading Mo94 from
/xs_libraries/fendl-3.2-hdf5/neutron/Mo94.h5
Reading Mo95 from
/xs_libraries/fendl-3.2-hdf5/neutron/Mo95.h5
Reading Mo92 from
/xs_libraries/fendl-3.2-hdf5/neutron/Mo92.h5
Reading Nb93 from
/xs_libraries/fendl-3.2-hdf5/neutron/Nb93.h5
Reading Nb from
/xs_libraries/fendl-3.2-hdf5/photon/Nb.h5 
Reading Sn118 from
/xs_libraries/fendl-3.2-hdf5/neutron/Sn118.h5
Reading Sn from
/xs_libraries/fendl-3.2-hdf5/photon/Sn.h5 
Reading Sn124 from
/xs_libraries/fendl-3.2-hdf5/neutron/Sn124.h5
Reading Sn116 from
/xs_libraries/fendl-3.2-hdf5/neutron/Sn116.h5
Reading Sn119 from
/xs_libraries/fendl-3.2-hdf5/neutron/Sn119.h5
Reading Sn120 from
/xs_libraries/fendl-3.2-hdf5/neutron/Sn120.h5
Reading Sn112 from
/xs_libraries/fendl-3.2-hdf5/neutron/Sn112.h5
Reading Sn122 from
/xs_libraries/fendl-3.2-hdf5/neutron/Sn122.h5
Reading Sn115 from
/xs_libraries/fendl-3.2-hdf5/neutron/Sn115.h5
Reading Sn114 from
/xs_libraries/fendl-3.2-hdf5/neutron/Sn114.h5
Reading Sn117 from
/xs_libraries/fendl-3.2-hdf5/neutron/Sn117.h5