Fission of heavy nuclei by linearly polarized photons

Abstract

Analysing power Σ data from photofission of ²³²Th, ²³³U, ²³5U, ²³⁶U, ²³⁸U at the region of giant resonance have been measured using linearly polarized photons. The polarized photons were obtained by plane channelling of electrons in a silicon single crystal. The analysing power Σ dependence of the mass number of even-even nucleus has been discovered. Comparison of the analysing power Σ values with the data from other experiments with both polarized and unpolarized photon beams was made. It is shown that the analysing power Σ values agree with the modern knowledge of E1 transitions but cannot be explain by domination any one of them. It is supposed that analysing power Σ is very sensitive to different relative inner and outer fission barrier heights and this affects on Σ values for even-even nuclei with the same Z.