|Message: PhotoNuclear Cross sections don't seem to be correct.||Not Logged In (login)|
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i was a bit discouraged to post any further messages in here since i never got replies the last time. anyway, hope it works this time.
I have enabled the PhotoNuclear process and all relevant components looking at gamma (10-80MeV) on 4He target.
I have disabled all of the gamma electromagantic processes so i can have a closer look at 4He breakup products. I also biased the cross section to get more statistics.
I found two problems which are connected to the photonuclear cross-section i guess:
1) Geant4 calculates the breakup energy thresholds correctly however, when the photon energy is high enough for 3-body break up, all of the 2-body processes stop. so, when the photon energy reach 26MeV (threshold for 3 body breakup) the 2 body breakup below 26MeV no longer produced.
2) Geant4 seems to use wrong cross sections for all reaction channels. I looked at the data in the G4PhotoNuclearCrossSection.cc and it looked correct for the total photoabsorption cross section in 4He but Geant4 doesnt seems to be generating events according to that cross section.
I have been working on this for few days and i'm giving up.
thank you all.
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