Geant4 simulation TEM electrons

I visited the Geant4 beginners course until recently. Now I am trying to implement everything into practice. I was running simulations on both a 30µm and a 50 µm silicon sensor with TEM electron energies of 160, 200 and 300 keV. The physical model I was using was FTFP_BERT_EMZ and I was usingbins of 0.1 keV intervals and 10 mio events. My colleage was running the same analysis using allpix squared using the same parameters. Nevertheless we significantly deviate especially the mean value at low energies (160 keV). The other value is the most probable value.
Does somebody know the correct values please?


which production cuts are being used in the two cases? Are they comparable? I would personally try to use the Opt4 constructor in the physics list, for increased precision.


Thank you very much for this hint: we took different production cuts

Hi Luciano, after your advice and also corrections in the geometry (which also differed) we became now very close together. Nevertheless we still see some (small) deviations.
Another question: from the existing physics list we took FTFP_BERT_EMZ. Since we are contemplating electrons in the 160keV to 300keV range (TEM electrons), wouldn’t it be better to use QBBC_EMZ instead?
kind regards

Hi Edi,

as you are interested only in electrons (i.e. EM physics), the models that you use for the hadronic physics do not matter very much. So the “EMZ” is the same in the two cases. As mentioned in the previous post, I would personally try to use the G4EmStandardPhysics_option4 constructor in the physics list, for increased precision in the EM physics.