[abcs12000]

شكرا لمرورك الكريم د.محمد[align=left]
in fission rxn on U-235 using low energy neutrons (.025eV)we get two fission fragments in the exit channel
one of the fragments is light and take more energy after rxn than the other fragment which is heavier
exU-235)+(n)=(Br-87)+(La-146-)+3(n)using slow neutrons
, when we using fast neutrons(>0.5MeV) we get two fission fragments with approximately same weight
what is the mechanism that make this difference?thanks[/align]