|Message: neutron reflection||Not Logged In (login)|
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I am experiencing in my simulations an high number of energy releases in my detector caused by neutrons, which i don't expect from my calculations
I made a test with a 40 um thick Bi slab, shooting 100 eV neutrons perpendicularly to the surface. The best estimate I have found for neutron cross section for 100 eV neutrons impact on Bi is ~10 barn [http://prl.aps.org/abstract/PRL/v36/i17/p1021_1], so I was expecting ~11 interactions inside the slahb for 10000 incident neutrons.
My detector records instead 237 energy releases, 10 inside the slab as I expect, and 227 on the slab surface (in the first 0.1 um). There is an high number of neutrons that bounce back on the detector surface, transfering energy to Bi nuclei and causing detections.
I don't know if this behaviour is to be expected or not, can someone enlight me on this matter?
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