FISSION FRAGMENT GAMMA-RAYS ANISOTROPY AND SOME CLASSICAL NUCLEAR PROPERTIES


L.S. El-Mekkawi, O.M.El Bakly

Hot Laboratory Centre, Atomic Authority of Egypt

The anisotropy of fission fragment gamma rays in the reaction 235U(nth,f) has been measured for gamma energy band 0.82-0.92 Mev. The anisotropy value was found to be 0.165+0.03. The data is corrected for Doppler effect and background and results were worked according to the theory of Strutinski. As it was found from cluster model, that nuclear viscosity should be zero from rigidity, anisotropy increases with mass of fissioning nucleus and fragment rotations due to Nix and Swiatski are absently. It was also found that there is a minimum rigidity for fissionable nuclei and that hard gamma rays result from clusters in a fissioning nucleus.