|Message: range cut for very thin layers||Not Logged In (login)|
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I am simulating the counting of 140keV gammas which go thru a geometry which consists of alternating Pb/Air layers which are very thin (0.1mm). A 4pi Gamma source illimunates this geometry from above, seeing the channels down. I am counting the gamma pass thru the channels (of Pb/Air) from the bottom (i.e., gammas not absorber/attenuated by the Pb layers).
However G4 simulation does not match the theoretical expected value. (20% or so higher than expected value even when the theory is adjusted for penetration/attenuation).
I am looking for reasons for discrepeancy. I used standard and LowEnergy EM physics lists with range cuts ranging from 1mm to 1micron.
Anyone has any ideas/directions as to where I should be looking to resolve this problem?
Thank you very much, Regards, Ahmet.
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